malloc fails when dealing with huge files

I'm using Git for a project that contains huge (multi-gigabyte) files.
 I need to track these files, but with some of the really big ones,
git-add aborts with the message "fatal: Out of memory, malloc failed".
 Also, git-gc sometimes fails because it can't allocate enough memory.
 I've been using the "--window-memory" option to git- repack to work
around the git-gc problem, but I don't know of a similar trick for
git-add.  Is there any way (aside from adding more memory, of course)
that I can deal with these huge files?  I'm using git 1.5.6.2 on
Debian 4.0.

Thanks in advance.

Jonathan Blanton