I'm not sure if this is going to be related to the deep think bug or not.
However, I've noticed since 7.0 or so whenever I log off in a sitting position, when I log back in, I'm standing and on the ground, not an object.
For example. If I'm in my Zen Garden, sitting on a chair contemplating my navel, and I log off, when I log back in, I'm standing on the ground below my garden, not on the 10x10 textured slab I use as the floor of the garden.
A second login type bug happened yesterday. I logged off while standing at RT66, logged back in and it was as if I had rubber legs (George Busch and Dionysis Starseeker witnessed it.) If I was still, I was standing fine, if I walked, it was as if I was walking while sitting. When I flew, I was able to "straighten up" and walk normal after landing.
Last night I logged off while sitting down in the Amplitheater (don't know if the sim froze or not. I was getting no response from it after Jen Linden's trivia contest so I eventaully quit SL.) If someone wants to email me a time when they can monitor what's going on, I'd be happy to try and recreate the sitting down login bug.