[El_Muerte]

be sure to also overwrite the functions_akismet.php when you upgrade/revert

anyway, there appears to be connections issues, the debug line should be either:
"Key = valid" or "Key = invalid"
if it doesn't contain any text then there was an error in connecting to the akismet server to validate the key.

the key isn't validated while you are typing, it will be validated when the text field loses focus, and when the options pages is loaded.

Besides, you can simply enter an invalid key and save the the options. The rest of the plugin will still try to check for spam and submit content despite a possible invalid key.