split hangs

[Jacek Popławski]

My program hangs when running that instruction:

ourlist=ourregex.split(s)

I can only kill it, or ctrl+z

ourregex is of course result of re.compile()

s is a long string

it works good with other strings, why it hangs with that one?
how can I fix it? how to find out what is bad?
how it's possible that split() hangs?

PS. python-1.5.2, Linux

-- 
Now the best steel goes through the fire
And you seem to burn
The dead man's always a liar                              "Hide In The Rainbow"
Look out! there's another one learning!                     - Ronnie James Dio