cpm crashes when trying to use gpg key with UTF-8 extended characters

[piontec]

When I'm using a gpg key which has the follwing identity
uid Żółw Słoń <email address hidden>
cpm ran using command:
cpm --key <email address hidden>
crashes with the following error message:
conversion failed for string 'Żółw Słoń' (-2). Segmentation fault

But when using id:
uid Zolw Slon <email address hidden>
everything works fine.

To reproduce, just generate gpg rsa&rsa 1024 keys with the given ids.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: cpm 0.26-1
ProcVersionSignature: Ubuntu 3.0.0-14.23-generic 3.0.9
Uname: Linux 3.0.0-14-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
Date: Wed Jan 11 20:48:03 2012
InstallationMedia: Kubuntu 10.04 "Lucid Lynx" - Beta amd64 (20100318)
ProcEnviron:
 LANGUAGE=
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: cpm
UpgradeStatus: Upgraded to oneiric on 2011-10-14 (89 days ago)

[Stig Sandbeck Mathisen (ssm)]

Forwarded upstream to https://github.com/comotion/cpm/issues/25