Imhotep has been sentenced to "the Nameless Death," yet his name is still inscribed on his coffin. The ancient Egyptians had chisels and should have been able to destroy the glyphs on the coffin that make up Imhotep's name, but it is untouched when his mummy is found.
In the flashback scenes of Imhotep being mummified, his legs are bandaged together. They are still bound together in long shots of the mummy in his sarcophagus (which was a dummy). But when he comes to life, his legs are bandaged separately, allowing him to walk.
According to the newspaper article detailing the findings, the man who helped them to find the site is named "Ardath Bay." (See also trivia, this is an anagram of "Death by Ra.") But many other sources, including the subtitles/captions on home video releases, use the spelling "Ardeth Bay."
It is said a few times in the movie that princess Ankh-es-en-amon was a vestal virgin. Vestal virgins were in fact part of the Roman religion (they were priestesses of the goddess Vesta, hence their name), and had nothing to do with ancient Egyptian religion.