urgent help?

[Arisandy Arief]

hi...
my Qmail server already run until 157 days but now...when I try send to some
mailbox the message didn't arrive until now?? why??
qmail-qstat :
------------
messages in queue: 17106
messages in queue but not yet preprocessed: 37

and now my /var/qmail/queue use 50% of partition?? before that just 3-10%
what should I do??

thanks...