diff -r 24100651daa9 -r 335a1bd18eed runtime/doc/options.txt
--- a/runtime/doc/options.txt	Tue Mar 23 18:22:46 2010 +0100
+++ b/runtime/doc/options.txt	Wed Apr 14 17:10:24 2010 +0200
@@ -4475,6 +4475,21 @@
 <	This option cannot be set from a |modeline| or in the |sandbox|, for
 	security reasons.
 
+			*'margincolumn'* *'mc'*
+'margincolumn' 'mc'	number	(default 0)
+			local to window
+			{not in Vi}
+			{not available when compiled without the  |+syntax|
+			feature}
+	Highlight a particular screen column with MarginColumn
+	|hl-MarginColumn|.  Useful to align text.  Will make screen redrawing
+	slower.
+        If 'margincolumn' < 0 then 'margincolumn' is set equal to 'textwidth'.
+	If you only want the highlighting in the current window you can use
+	these autocommands: >
+		au WinLeave * set mc=0
+		au WinEnter * set mc=81
+
 						*'matchpairs'* *'mps'*
 'matchpairs' 'mps'	string	(default "(:),{:},[:]")
 			local to buffer
diff -r 24100651daa9 -r 335a1bd18eed src/option.c
--- a/src/option.c	Tue Mar 23 18:22:46 2010 +0100
+++ b/src/option.c	Wed Apr 14 17:10:24 2010 +0200
@@ -227,6 +227,7 @@
 #ifdef FEAT_SYN_HL
 # define PV_CUC		OPT_WIN(WV_CUC)
 # define PV_CUL		OPT_WIN(WV_CUL)
+# define PV_MC		OPT_WIN(WV_MC)
 #endif
 #ifdef FEAT_STL_OPT
 # define PV_STL		OPT_BOTH(OPT_WIN(WV_STL))
@@ -450,7 +451,7 @@
 #if defined(FEAT_DIFF) || defined(FEAT_FOLDING) || defined(FEAT_SPELL) \
 	|| defined(FEAT_VERTSPLIT) || defined(FEAT_CLIPBOARD) \
 	|| defined(FEAT_INS_EXPAND) || defined(FEAT_SYN_HL)
-# define HIGHLIGHT_INIT "8:SpecialKey,@:NonText,d:Directory,e:ErrorMsg,i:IncSearch,l:Search,m:MoreMsg,M:ModeMsg,n:LineNr,r:Question,s:StatusLine,S:StatusLineNC,c:VertSplit,t:Title,v:Visual,V:VisualNOS,w:WarningMsg,W:WildMenu,f:Folded,F:FoldColumn,A:DiffAdd,C:DiffChange,D:DiffDelete,T:DiffText,>:SignColumn,B:SpellBad,P:SpellCap,R:SpellRare,L:SpellLocal,+:Pmenu,=:PmenuSel,x:PmenuSbar,X:PmenuThumb,*:TabLine,#:TabLineSel,_:TabLineFill,!:CursorColumn,.:CursorLine"
+# define HIGHLIGHT_INIT "8:SpecialKey,@:NonText,d:Directory,e:ErrorMsg,i:IncSearch,l:Search,m:MoreMsg,M:ModeMsg,n:LineNr,r:Question,s:StatusLine,S:StatusLineNC,c:VertSplit,t:Title,v:Visual,V:VisualNOS,w:WarningMsg,W:WildMenu,f:Folded,F:FoldColumn,A:DiffAdd,C:DiffChange,D:DiffDelete,T:DiffText,>:SignColumn,B:SpellBad,P:SpellCap,R:SpellRare,L:SpellLocal,+:Pmenu,=:PmenuSel,x:PmenuSbar,X:PmenuThumb,*:TabLine,#:TabLineSel,_:TabLineFill,!:CursorColumn,.:CursorLine,g:MarginColumn"
 #else
 # define HIGHLIGHT_INIT "8:SpecialKey,@:NonText,d:Directory,e:ErrorMsg,i:IncSearch,l:Search,m:MoreMsg,M:ModeMsg,n:LineNr,r:Question,s:StatusLine,S:StatusLineNC,t:Title,v:Visual,w:WarningMsg,W:WildMenu,>:SignColumn,*:TabLine,#:TabLineSel,_:TabLineFill"
 #endif
@@ -1677,6 +1678,13 @@
 			    {(char_u *)NULL, (char_u *)0L}
 #endif
 			    SCRIPTID_INIT},
+    {"margincolumn", "mc",  P_NUM|P_VI_DEF|P_RWIN,
+#ifdef FEAT_SYN_HL
+			    (char_u *)VAR_WIN, PV_MC,
+#else
+			    (char_u *)NULL, PV_NONE,
+#endif
+			    {(char_u *)0L, (char_u *)0L} SCRIPTID_INIT},
     {"matchpairs",  "mps",  P_STRING|P_ALLOCED|P_VI_DEF|P_COMMA|P_NODUP,
 			    (char_u *)&p_mps, PV_MPS,
 			    {(char_u *)"(:),{:},[:]", (char_u *)0L}
@@ -2485,7 +2493,7 @@
 			    (char_u *)FALSE,
 #endif
 				(char_u *)0L} SCRIPTID_INIT},
-    {"textwidth",   "tw",   P_NUM|P_VI_DEF|P_VIM,
+    {"textwidth",   "tw",   P_NUM|P_VI_DEF|P_VIM|P_RWIN,
 			    (char_u *)&p_tw, PV_TW,
 			    {(char_u *)0L, (char_u *)0L} SCRIPTID_INIT},
     {"thesaurus",   "tsr",  P_STRING|P_EXPAND|P_VI_DEF|P_COMMA|P_NODUP,
@@ -9190,6 +9198,7 @@
 #ifdef FEAT_SYN_HL
 	case PV_CUC:	return (char_u *)&(curwin->w_p_cuc);
 	case PV_CUL:	return (char_u *)&(curwin->w_p_cul);
+	case PV_MC:	return (char_u *)&(curwin->w_p_mc);
 #endif
 #ifdef FEAT_DIFF
 	case PV_DIFF:	return (char_u *)&(curwin->w_p_diff);
@@ -9417,6 +9426,7 @@
 #ifdef FEAT_SYN_HL
     to->wo_cuc = from->wo_cuc;
     to->wo_cul = from->wo_cul;
+    to->wo_mc = from->wo_mc;
 #endif
 #ifdef FEAT_DIFF
     to->wo_diff = from->wo_diff;
diff -r 24100651daa9 -r 335a1bd18eed src/option.h
--- a/src/option.h	Tue Mar 23 18:22:46 2010 +0100
+++ b/src/option.h	Wed Apr 14 17:10:24 2010 +0200
@@ -1059,6 +1059,7 @@
 #ifdef FEAT_SYN_HL
     , WV_CUC
     , WV_CUL
+    , WV_MC
 #endif
 #ifdef FEAT_STL_OPT
     , WV_STL
diff -r 24100651daa9 -r 335a1bd18eed src/screen.c
--- a/src/screen.c	Tue Mar 23 18:22:46 2010 +0100
+++ b/src/screen.c	Wed Apr 14 17:10:24 2010 +0200
@@ -2622,6 +2622,9 @@
     int		has_syntax = FALSE;	/* this buffer has syntax highl. */
     int		save_did_emsg;
     int		eol_hl_off = 0;		/* 1 if highlighted char after EOL */
+    int		margin_vcol = 0;	/* ('margincolumn'-1) (= 0 based col)*/
+    int		draw_margin_col = 0;	/* Only highlight margincolumn if 1*/
+    int		rightmost_vcol;		/* rightmost vcol that needs to draw */
 #endif
 #ifdef FEAT_SPELL
     int		has_spell = FALSE;	/* this buffer has spell checking */
@@ -4497,6 +4500,23 @@
 	if (c == NUL)
 	{
 #ifdef FEAT_SYN_HL
+	    if (wp->w_p_mc > 0)
+	    {
+		margin_vcol = wp->w_p_mc - 1;
+		draw_margin_col = 1;
+	    }
+	    else if (wp->w_p_mc < 0
+		     && curbuf->b_p_tw > 0)
+	    {
+		margin_vcol = curbuf->b_p_tw;
+		draw_margin_col = 1;
+	    }
+	    else
+	    {
+		margin_vcol = -1;
+		draw_margin_col = 0;
+	    }
+
 	    if (eol_hl_off > 0 && vcol - eol_hl_off == (long)wp->w_virtcol
 		    && lnum == wp->w_cursor.lnum)
 	    {
@@ -4506,25 +4526,33 @@
 		--vcol;
 	    }
 
-	    /* Highlight 'cursorcolumn' past end of the line. */
+	    /* Highlight 'cursorcolumn' & 'margincolumn' past end of the line */
 	    if (wp->w_p_wrap)
 		v = wp->w_skipcol;
 	    else
 		v = wp->w_leftcol;
+
 	    /* check if line ends before left margin */
 	    if (vcol < v + col - win_col_off(wp))
-
 		vcol = v + col - win_col_off(wp);
-	    if (wp->w_p_cuc
+
+	    if (((wp->w_p_cuc
 		    && (int)wp->w_virtcol >= vcol - eol_hl_off
 		    && (int)wp->w_virtcol < W_WIDTH(wp) * (row - startrow + 1)
 									   + v
-		    && lnum != wp->w_cursor.lnum
+		    && lnum != wp->w_cursor.lnum)
+			|| (draw_margin_col
+			    && margin_vcol >= vcol - eol_hl_off
+			    && margin_vcol < W_WIDTH(wp) * (row - startrow + 1)
+			    + v))
 # ifdef FEAT_RIGHTLEFT
 		    && !wp->w_p_rl
 # endif
 		    )
 	    {
+		rightmost_vcol = (margin_vcol > (long)wp->w_virtcol) ?
+		    margin_vcol : wp->w_virtcol;
+
 		while (col < W_WIDTH(wp))
 		{
 		    ScreenLines[off] = ' ';
@@ -4533,12 +4561,22 @@
 			ScreenLinesUC[off] = 0;
 #endif
 		    ++col;
-		    if (vcol == (long)wp->w_virtcol)
+		    if (wp->w_p_cuc && vcol == (long)wp->w_virtcol)
 		    {
-			ScreenAttrs[off] = hl_attr(HLF_CUC);
+			ScreenAttrs[off++] = hl_attr(HLF_CUC);
+		    }
+		    else if (draw_margin_col && vcol == margin_vcol)
+		    {
+			ScreenAttrs[off++] = hl_attr(HLF_MC);
+		    }
+		    else
+		    {
+			ScreenAttrs[off++] = 0;
+		    }
+
+		    if (vcol >= rightmost_vcol)
 			break;
-		    }
-		    ScreenAttrs[off++] = 0;
+
 		    ++vcol;
 		}
 	    }
@@ -4596,8 +4634,27 @@
 	}
 
 #ifdef FEAT_SYN_HL
+	if (wp->w_p_mc > 0)
+	{
+	    margin_vcol = wp->w_p_mc - 1;
+	    draw_margin_col = 1;
+	}
+	else if (wp->w_p_mc < 0
+		 && curbuf->b_p_tw > 0)
+	{
+	    margin_vcol = curbuf->b_p_tw;
+	    draw_margin_col = 1;
+	}
+	else
+	{
+	    draw_margin_col = 0;
+	}
+
+	vcol_save_attr = -1;
 	/* Highlight the cursor column if 'cursorcolumn' is set.  But don't
-	 * highlight the cursor position itself. */
+	 * highlight the cursor position itself.
+	 * Also highlight the 'margincolumn' if it is different than
+	 * 'cursorcolumn' */
 	if (wp->w_p_cuc && vcol == (long)wp->w_virtcol
 		&& lnum != wp->w_cursor.lnum
 		&& draw_state == WL_LINE
@@ -4606,8 +4663,13 @@
 	    vcol_save_attr = char_attr;
 	    char_attr = hl_combine_attr(char_attr, hl_attr(HLF_CUC));
 	}
-	else
-	    vcol_save_attr = -1;
+	else if (draw_margin_col && vcol == margin_vcol
+		&& draw_state == WL_LINE
+		&& !lnum_in_visual_area)
+	{
+	    vcol_save_attr = char_attr;
+	    char_attr = hl_combine_attr(char_attr, hl_attr(HLF_MC));
+	}
 #endif
 
 	/*
diff -r 24100651daa9 -r 335a1bd18eed src/structs.h
--- a/src/structs.h	Tue Mar 23 18:22:46 2010 +0100
+++ b/src/structs.h	Wed Apr 14 17:10:24 2010 +0200
@@ -200,6 +200,8 @@
 # define w_p_cuc w_onebuf_opt.wo_cuc	/* 'cursorcolumn' */
     int		wo_cul;
 # define w_p_cul w_onebuf_opt.wo_cul	/* 'cursorline' */
+    long	wo_mc;
+# define w_p_mc w_onebuf_opt.wo_mc	/* 'margincolumn' */
 #endif
 #ifdef FEAT_STL_OPT
     char_u	*wo_stl;
diff -r 24100651daa9 -r 335a1bd18eed src/syntax.c
--- a/src/syntax.c	Tue Mar 23 18:22:46 2010 +0100
+++ b/src/syntax.c	Wed Apr 14 17:10:24 2010 +0200
@@ -6315,6 +6315,8 @@
 	     "CursorColumn term=reverse ctermbg=LightGrey guibg=Grey90"),
 	CENT("CursorLine term=underline cterm=underline",
 	     "CursorLine term=underline cterm=underline guibg=Grey90"),
+	CENT("MarginColumn term=reverse ctermbg=Red",
+	     "MarginColumn term=reverse ctermbg=Red guibg=Red"),
 #endif
 #ifdef FEAT_AUTOCMD
 	CENT("MatchParen term=reverse ctermbg=Cyan",
@@ -6395,6 +6397,8 @@
 	     "CursorColumn term=reverse ctermbg=DarkGrey guibg=Grey40"),
 	CENT("CursorLine term=underline cterm=underline",
 	     "CursorLine term=underline cterm=underline guibg=Grey40"),
+	CENT("MarginColumn term=reverse ctermbg=DarkRed",
+	     "MarginColumn term=reverse ctermbg=DarkRed guibg=DarkRed"),
 #endif
 #ifdef FEAT_AUTOCMD
 	CENT("MatchParen term=reverse ctermbg=DarkCyan",
diff -r 24100651daa9 -r 335a1bd18eed src/vim.h
--- a/src/vim.h	Tue Mar 23 18:22:46 2010 +0100
+++ b/src/vim.h	Wed Apr 14 17:10:24 2010 +0200
@@ -1276,6 +1276,7 @@
     , HLF_TPF	    /* tabpage line filler */
     , HLF_CUC	    /* 'cursurcolumn' */
     , HLF_CUL	    /* 'cursurline' */
+    , HLF_MC	    /* 'margincolumn' */
     , HLF_COUNT	    /* MUST be the last one */
 } hlf_T;
 
@@ -1285,7 +1286,7 @@
 		  'n', 'r', 's', 'S', 'c', 't', 'v', 'V', 'w', 'W', \
 		  'f', 'F', 'A', 'C', 'D', 'T', '>', \
 		  'B', 'P', 'R', 'L', \
-		  '+', '=', 'x', 'X', '*', '#', '_', '!', '.'}
+		  '+', '=', 'x', 'X', '*', '#', '_', '!', '.', 'g'}
 
 /*
  * Boolean constants