4.5.0.2 ? what's in captcha settings? that might have happened because you used variable in captcha settings and that variable had wrond value.
Yes i have variable in captcha settings but i have right value in there. 110%
Also tested without variable and getting same problem...
Tested with DeathByCaptcha and ImageDecoders. - Both have this problem.
Not everytime as i sad but offten i'm getting error.
Actually i noticed that there is problems what i using The best spinner together with zenno... Do not know is that problem in this case.
But i need solution for that