I have this problem and it also happen in the ElXTree Megademo on the Inplace Editors page:
1. Click on "Armstrong". On the MouseDown it turns blue. On the MouseUp the text becomes grey, background is shadowed, and the box is circled in blue dots, and blinking cursor is at the end of the word. This is basically okay (although I don't think the initial highlighting in blue before editing should happen - and is related to another question I had in another post).
2. Without clicking, move the mouse off of the inplace editor and then back onto it. The inplace editor now becomes highlighted in blue with white letters. This is wrong. Either start it with these colors, or leave them as grey.
Also, you may notice the inplace editor flashing quickly in blue as you move the mouse off it. This happens sometimes but not all the time - I don't know why. But it shouldn't happen either.