From: thug@phantom.com (Murdering Thug)

Yes I do think the idea of making a "more random than random" stream by filtering out long runs of 0's or 1's weakens the the key stream in theory, but in practical use it strengthens it, because if the stream is left alone, runs of 500 bits of 0's or 1's can come through, and any fool can then extract plain text using XOR in this area of the cyphertext.

The odds against a run of 500 1's is one in 2^500th, which is a number so large I can't imagine a real random number source creating it in the lifetime of our universe. Presumably, your problem is that your random number source is crap. Perry