Gnome GCR won't unlock p12 certificate with password length > 31 characters

I am unable to import a p12 s/mime certificate using gcr if the certificate is encrypted with a password containing 32 or more characters. When trying to unlock the certificate, gcr responds as if the password entered was incorrect.

I imagine somewhere a 32-byte variable is being used for the password string, but that is just a guess.

Process to reproduce:
Export a certificate from Firefox/Thunderbird (or generate your own).
Encrypt it with the password '1234567890123456789012345678901' (31 characters).
Open with gcr and unlock successfully.
Export the same certificate.
Encrypt it with the password '12345678901234567890123456789012' (32 characters).
Open with gcr and unlock. Password is rejected.

1.
Description: Linux Mint 17 Qiana
Release: 17

2.
gcr:
  Installed: 3.10.1-1
  Candidate: 3.10.1-1
  Version table:
 *** 3.10.1-1 0
        500 http://archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages
        100 /var/lib/dpkg/status

3. I expected the 30, 31, 32, 33, 35, and 40 length passwords to be accepted and the certificate to be imported.

4. Only the certificates with password lengths of 31 characters or fewer were unlocked and imported . Certificates with 32 characters or more resulted in the error message "The password was incorrect" when trying to unlock, even though the password was, in fact, correct.