Michelle Rodriguez & Zac Efron Partying -- Workin' The Pole During Makeout Sesh

Michelle Rodriguez is treating herself to an early birthday present -- Zac Efron -- the two were all over each other Monday during a night of hard partying in Sardinia.

Michelle -- who turns 36 Saturday -- and the 26-year-old "Neighbors" star hit up a club in Porto Cervo off the coast of Italy ... and if there was any doubt they're banging, well ...

The photog says Michelle was drinking and smoking and had to steady herself at times ... grabbing onto an overhead pole while Zac slobbered all over her.