PM-
you can do it through a shell script
--------------------------------
var shell = "/bin/sh";
var file = Components.classes["@mozilla.org/file/local;1"]
.createInstance(Components.interfaces.nsILocalFile);
file.initWithPath(shell);
var process = Components.classes["@mozilla.org/process/util;1"]
.createInstance(Components.interfaces.nsIProcess);
process.init(file);
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found at http://forums.mozillazine.org/viewtopic.php?f=19&t=663377
oops, missed the last two lines of code:
var args = ["path/to/script","arg1","arg2","etc"];
process.run(false, args, args.length);