It's a rumour and if it was in the Cinema version it isn't in the DVD, as i too heard the rumour and spent a couple of hours watching it intensly just to be sure. (I'm very sad and when i 'get a bee in my bonet' nothing will stop me untill i discover the truth, which is why i'm banned from entering Roswell). So long story short there are no pictures other than fake ones that have obviously spent time in photoshop.
"Beware the form-fitting black armor-clad Drow hottie with twin Mineral II Greensteel Khopeshes!"
"Liella d'Orien says, '"You're the fool, Devil. -- Witness the power of this fully ARMED and OPERATIONAL Titan!"'"
I'm sure they'd run into copyright problems if they tried something like that. I know there are a few other gag crossover references (i.e., the Maltese Falcon in Palpatine's office), but isn't Joss Whedon supposed to be really protective of his stuff or something?