Why?
As of
this page, it seems like it was removed from testing due to a grave bug that could lead to filesystem corruption.
This has now been corrected since February 2006. Unfortunatly since this time, this package has not gone under the threshold to be accepted again in testing, so it stayed in unstable for more testing, while the previous stable sarge version could still be used.
On the 7 of december, a new release candidate appeared. Unfortunatly 4 days after testing entered in frozen state, 10 days are required for a package to enter in testing, without more RC-bugs than the previous testing version.
If the package (in previous version then) was without new bugs, then it should have entered
See
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=367966
Try the unstable version?