Unable to find stream pointer

Hi PHP-Developers, i am sending this mail to php-dev because nobody seems to know an answer in php-general and i did not find anything in the archives. Maybe it is a bug in the imap-routine. I am having problems with php and imap now for several days on several servers. I just get the following Error: Warning: Unable to find stream pointer in <file> on line <line> This error does not occur in every execution, but only sometimes. I read a lot about this error on the internet, but i still don't know what is the reason for this error and how to work around it. Does anybody of you know where this error originates? thanx andreas