Inkscape 0.48 on Windows 7 64-bit
Open the edit history panel.
Press Ctrl+Y to redo.
When you enable snapping, a blank entry appears in the edit history, but inkscape doesn't jump to the blank entry as it normally does, and the blank entry doesn't appear until you try to redo. Trying to click on other entries in the edit history sometimes causes jumps to the blank entry, and sometimes Redo causes the edit history panel to jump around wildly.
There is probable memory corruption.