crossfades not working

i am using ardour v. 2.5 (built from revision 3525) and the crossfade function is not working.
i have crossfades activated in the options menu, but i am not getting any crossfades. my regions are set to opaque.
am i missing something? i searched the archives for any mention of this, but haven’t found anything.
i am on ubuntu 8.04.
thanks in advance for any help!

this is mysterious…i re-started ardour–without making any changes in settings–and now the crossfades are there again.
is this a bug?