Who said Germans don't have a sense of humor? We've been listening to ex- UBS ( UBS) CEO Oswald Gruebel for the past week and we think he is simply hilarious! Shares of beleaguered Swiss bank UBS spiked 8% on Monday as the company named Sergio Ermotti as interim CEO after a $2.3 billion rogue trading loss forced the resignation of Oswald Gruebel over the weekend. Gruebel was so confident that he would stay on as the bank's leader that he chuckled last Wednesday when a Reuters reporter asked if he still had the board's support, replying, "Yes. Always." Always? Oh boy, that's hysterical Oswald! You didn't even make it through the weekend! We should call you "Ossie the Owl" from now on because you sure are a hoot. And that was not even the funniest thing he said prior to his sacking. Barely a week ago, Gruebel told Swiss weekly Der Sonntag about the scandal, "I'm responsible for everything that happens at the bank, but if you ask me whether I feel guilty, then I would say no." Not guilty huh? Well, maybe good old Ossie was just pulling their proverbial leg back then, because he certainly sang a different tune in his final memo to his staff this weekend. "As CEO, I bear full responsibility for what occurs at UBS. From my first day on the job I placed the reputation of the bank above all else. That is why I want to and must act according to my convictions." Looking back, perhaps Gruebel's most side splitting remark came this past June when he said "we have no undue risk in our positions... I'm pretty convinced that we have one of the best risk managements in the industry." Man, what a laugher. Just too comical. But what really cracks us up about that particular statement is not that he announced a $2.3 billion rogue trading loss barely two months later. It's that he said it with a perfectly straight face.