Hi,
I am playing with gnu.regexp these days and finding more and more
to do before it becomes comparable with Sun's JDK.
Although I will continue to make efforts on gnu.regexp,
I am beginning to try another thing.
I have found oniguruma, the regex library which is used as a
regex engine of Ruby, is pretty good. It already supports
most part of java.util.regex.Pattern syntax.
http://www.geocities.jp/kosako3/oniguruma/
I will write a JNI interface to oniguruma, and make it
switchable with gnu.regexp. Users can select one of the
supported regexp engines at their choice.