Missing an achievement

[Balls-of-Steel]

I recently completed Vessel at 100%

In my library, it shows up that i have done 20/20 achievements, but when i click to see the achievements, it only show's 19 out of 20!
And the weirdest thing is that the achievement missing is the one to collect all the protoplasm in the mines, but it shows up the one of collecting all the protoplasm in the game!

Here is a screen:
http://img707.imageshack.us/img707/332/ls90.png

Please, help!

[Showboat]

I have the same problem - no solution yet