Happy Birthday, Samantha Ronson!

Who says that Samantha Ronson is a joyless husk of a human being?

Lindsay Lohan’s tune-spinning companion turned 31 yesterday, and the sometimes-happy couple celebrated in high style.

LiLo and Sam threw a bash at a West Hollywood lingerie store (no, really), with an ice-cream truck parked outside so the guests could indulge in sweet, sticky refreshments when the urge hit them.

At one point Lindsay, ever the prankster, playfully held a fake ice-cream cone up to her knocker. When Ronson, tastefully decked out in her dressiest Guns N’ Roses T-shirt, went in for a lick, Lohan jokingly popped the top off of the cone. What a laff-riot! Those two should really have their own act in Vegas.

Adding credence to recent rumors that the two are preparing for a same-sex marriage, Lindsay flaunted a diamond engagement ring as she left the party hand-in-hand with her gal.

Ain’t love grand? And it’s refreshing in this modern age that some people can throw a birthday party without any of the guests ending up dead from a head wound.