Filter in Thunderbird.

Hi. On my SuSE 9.2 I have set some filters up in Thunderbird, to put mails comming from various mailinglist to directories I have made. This is the first time it hasn't worked ok. The problem is, that I need to enter the filter every time, I have some mails to be transfered to their respective dir's, and from here to manually select "run now", to get the mails into their directories. As they are transfered ok then tells me, that the filters has been made ok. But what could be the reason ?. The Thunderbird is the version 0.9 Erik Jakobsen