Recent versions of artifactory are requiring the use of postgres 9.2 or better. Since both RHEL 6 and vmware's vpostgres are based on 9.1 you cannot use the packages shipped by the distributors with artifactory.
As far as I can tell the only incompatibility is the database creation scripts have one call to the LEFT() function. Other than that artifactory works fine on the older database releases.
Since the change is trivial (change LEFT(var, len) to substr(var, 1, len)) and supporting the vendor's package release is useful, the change should be made.