Changing regex implementation in LineContainsRegExp filter

[Alex Egg]

By default it looks like the LineContainsRegExp filter uses the
java.util.regex package by default. However, apparently
this particular regex implementation doesn't support * metacharacters
in look-behinds, e.g.: (?<=\<script
.*src=\")[^\"]+(?=\".*\</script\>)
How can I change the implementation?

Thanks,
Alex