Safari logs me out very often since IOS5

Since i have installed IOS 5 it's just impossible to write a message on a phpbb site because of the bug of safari that keeps logging me out.

I tried to delete all cookies and history, i shutted down the ipad but it's still there...

I found a very similar problem on the forum about a cookie bug on safari (mac os version) but it's apparently not solved...

I had the same problem on the precedent version but it was less often. It's not casual anymore, i just can't continue like this.

I think it's a major bug on a device which like ipad is designed for friendly navigation on the internet. Using phpbb may be 40 % of my activities on it.

I'll just abandon the browser if i can't find a fix or a solution.

Any ideas ?