max uid value

I'm just finish some tests and review source code Solaris useradd.
I found on Solaris (>=9) limit for maximum UID/GID value.

$ grep UID /usr/include/limits.h 
#define UID_MAX         2147483647      /* max value for a user or group ID */

In case Solaris detecting UID/GID overflow is simple because after convert string to numeric value it only requires compare with UID_MAX.
I see now one things now which must be tested/resolved before prepare correct fix http://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=198920:

Is it on Linux also must be used Solaris limit for maximum UID/GID value or not ?

If yes: before fixing above bug probably must be fixed glibc for add above UID_MAX.
I can't find anything about maximum value uid/gid in glib code but I thing for save good interoperability with Solaris (for example on using NFS).

Comments ?

kloczek