I just did the PAR-thing last week, and I had some degree of trouble with Digest::MD5, of which I'm almost certain sha1.c would be a part. (SHA is a hash algorithim.)

So, I can't give you specific advice other than to look in that direction -- make sure you get a clean 'make test', etc.. Sorry I can't be more helpful but I'm on the road (with low battery no less :( )