Incorrect version comparison

[Marcus Ahlberg]

My daily cronscript reported this morning that there was a new  
version of ruby+pthreads:
ruby+pthreads-1.8.5.12,1            <   needs updating (index has  
1.8.6,1)

However, when I was about to upgrade it, it didn't appear in the list  
of outdated ports. Instead I saw this output from portversion:
ruby+pthreads-1.8.5.12,1    >  succeeds port (port has 1.8.6)

It appears that (1.8.6,1) has been replaced by (1.8.6) during the day  
and this has inaccurately taged my (1.8.5)-installation as newer than  
the one in ports. What might be the cause of this?

/Marcus Ahlberg