gaphor: Uninstallable because of dependencies with python

[ice]

Package: gaphor
Severity: grave
Justification: renders package unusable

When trying to install gaphor:
The following packages have unmet dependencies:
  gaphor: Depends: python (< 2.4) but 2.4-0ubuntu2 is to be installed
          Depends: python-diacanvas2 but it is not going to be installed
	    
I think it should depend python2.3, not python < 2.4 

-- System Information:
Debian Release: 3.1
Architecture: i386 (i686)
Kernel: Linux 2.6.8.1-2-386
Locale: LANG=es_ES at euro, LC_CTYPE=es_ES at euro (charmap=ISO-8859-15)