It's a Hack?

[PHCC]

Look This:

Its real or a hack??

 

[Cinefast]

It's real, however anyone can easily do that by cracking open the source code and in d_clisrv.h changing #define SUBVERSION 004 to whatever.

 

[Ezer'Arch]

RC2 = release candidate 2

And: http://mb.srb2.org/showthread.php?t=32879

 

[Prime 2.0]

The server you saw was a modified EXE that changed the version number. You are more interested in the new tooltip on the version number, which tells you more about the executable being used.