Problem:
Trying to create a capped collection on a 32bit system, user saw the following

> db.createCollection("test",

{capped:true, size:1000000000}

);

{ "errmsg" : "exception: bad new extent size", "code" : 10358, "ok" : 0 }

Total size of the file-system is less than 2GB

ls -lH
total 721640
rw------ 1 root root 16777216 Jul 14 09:04 local.0
rw------ 1 root root 33554432 Jul 14 09:03 local.1
rw------ 1 root root 67108864 Jul 14 09:55 local.2
rw------ 1 root root 16777216 Jul 14 09:48 local.ns
-rwxr-xr-x 1 root root 5 Jul 14 09:02 mongod.lock
rw------ 1 root root 16777216 Jul 14 09:34 test.0
rw------ 1 root root 33554432 Jul 14 09:34 test.1
rw------ 1 root root 536870912 Jul 14 09:34 test.2
rw------ 1 root root 16777216 Jul 14 09:34 test.ns

See also

http://groups.google.com/group/mongodb-user/browse_thread/thread/7f65692c3dd84e1d