If Cubes is right on what you're doing, I suggest you strip out all <script...> tags - whatever the scripting language. Here's a regex for this: 
$text =~ s/<SCRIPT[^>]>     # the opening <SCRIPT...> tag
           .*?              # as few chars as possible until...
           (?:</SCRIPT>|$)  # closing script tag or the end of the tex
+t ($)
          //xgis;           # (x) comments (g)lobal, case (i)nsensitiv
+e,
                            # treat string as (s)ingle line

# uncommented version
$text =~ s/<SCRIPT[^>]>.*?(?:</SCRIPT>|$)//gis;

[download]

You need to check for strings that don't contain a closing tag, as this example below shows: 

# imagine the following are two consecutive posts on a bulletin board

$first_post = <<_END_;
<SCRIPT LANGUAGE="Javascript">
document.location.href = "http://www.hamsterdance.com"
/*
_END_

$second_post = <<_END_;
*/
</SCRIPT>
_END_

[download]

I actually used this once :)

HTH

cLive ;-)

In reply to Re: Checking forms for JavaScript by cLive ;-)
in thread Checking forms for JavaScript by Sullust

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