builing mono fails on 10.5.8

[Thomas Ruedas]

Hi,
I am trying to build mono under OS 10.5.8 and get this rather useless error:
--->  Computing dependencies for mono
--->  Building mono
Error: org.macports.build for port mono returned: command execution failed
To report a bug, follow the instructions in the guide:
     http://guide.macports.org/#project.tickets
Error: Processing of port mono failed

I have tried to find some information about build failures but didn't 
get very far; I don't even know where to look for more detailed error 
messages, as the content of 
/opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_ports_devel_mono/mono/main.log 
is also rather unconspicuous. Any ideas? Should I file a bug right away?
Thomas