Evolution, GPG and a greyed out OK button

[dorward]

Running Evolution 2.2.3 and GPG 1.4.2, if I go to the Security tab on an account preferences dialog (for both accounts I have) then it starts out with the OK button being clickable.

The moment I enter any data into the Key ID field, the OK button gets greyed out. It remains this way even if I enter a valid GPG key, or erase everything I entered into the box.

Any ideas why this might be happening? And how I can fix it?