SW2008 at SP4 but Workgroup PDM at SP0

I am a user testing out PDM.
My VAR pointed out to that we are are out of synch, using SW2008 atSP4 but our PDM is only at SP0. In the SW support downloads I don'tsee any update listed SW2008 SP4. Is there someplace else to findthis, should I look at some other way to update?SolidworksWorkgroup Pdm