OT: building rpm file

[beast <beast ldap or id>]

I've just got the perl-gtk tarbal, how do I make the rpm package? do I 
need to change something on the source?
TIA.

[root devil tmp]# rpmbuild -ta Glib-1.141.tar.gz
error: Name field must be present in package: (main package)
error: Version field must be present in package: (main package)
error: Release field must be present in package: (main package)
error: Summary field must be present in package: (main package)
error: Group field must be present in package: (main package)
error: License field must be present in package: (main package)

--beast