Help with a filter/rule

[ramond...@gmail.com]

Hi all,

I would like to define a rule that filters out certain request
parameter from the request
so for example:

from:
localhost/contextpath/aaa/bbb/new?par1=xxx&par2=yyy&par3=zzz&par4=abc

to:
localhost/contextpath/aaa/bbb/new?par1=xxx&par4=abc

or
from:
localhost/contextpath/aaa/bbb/new?par4=abc&par2=zzz&par3=yyy&par1=xxx

to:
localhost/contextpath/aaa/bbb/new?par1=xxx&par2=zzz

The only thing I know for sure are the names of the request params
that I want to delete, I dont know the names of the (possible) other
parameters and I also cant tell up front at what place in the
querystring they appear (so dont know the order of the params in the
querystring)

tnx in advanced for your help
Ramon