I've patched manually the problem editing the file /usr/share/gdecrypt/main.py and changing the first line:
#!/usr/bin/env python2.5
By: #!/usr/bin/env python2
I've patched manually the problem editing the file /usr/share/ gdecrypt/ main.py and changing the first line:
#!/usr/bin/env python2.5
By:
#!/usr/bin/env python2