APT stopped working - MMap ran out of room

[Hamid <mylists@spils.com>]

Hi

I just added a new line to source.list in /etc/apt and then entered
# apt-get update

And now I have a nasty message:
----------------------------
Reading Package Lists... Error!
E: Dynamic MMap ran out of  room
E: Error occured while processing trophy (NewVersion1)
E: Problem wiith MergeList 
/var/lib/apt/lists/debian.lcs.mit.edu_debian_dists_unstable_main_binary-i386_Packages
E: The package lists or status file could not be parsed or opened
------------------------------
As far as the mentioned file is concerned, I have it in that folder with 
almost a size of 8 MB

Any help is appreciated
Thanks
Hamid