As an example, take the current version of kde_projects.xml, which is malformed (cuts off early at line 11861). Running kdesrc-build on a kde-projects module gives an error like this:

kde-svn@midna ~ $ kdesrc-build kde-workspace
 * Downloading projects.kde.org project database...
Encountered an error in the execution of the script.
The error reported was 
no element found at line 11861, column 0, byte 594603 at /home/kde-svn/perl5/perlbrew/perls/perl-blead/lib/site_perl/5.15.9/x86_64-linux/XML/Parser.pm line 187.
 at /home/kde-svn/perl5/perlbrew/perls/perl-blead/lib/site_perl/5.15.9/x86_64-linux/XML/Parser/Expat.pm line 479.
        XML::Parser::Expat::parse('XML::Parser::Expat=HASH(0x1c1f4e0)', 'GLOB(0x1f58c78)') called at /home/kde-svn/perl5/perlbrew/perls/perl-blead/lib/site_perl/5.15.9/x86_64-linux/XML/Parser.pm line 187
        eval {...} called at /home/kde-svn/perl5/perlbrew/perls/perl-blead/lib/site_perl/5.15.9/x86_64-linux/XML/Parser.pm line 186
        XML::Parser::parse('XML::Parser=HASH(0x1c0b590)', 'GLOB(0x1f58c78)') called at /kdesvn/src/extragear/utils/kdesrc-build/kdesrc-build line 1364
        KDEXMLReader::getModulesForProject('KDEXMLReader=HASH(0x21822a0)', 'kde-workspace', 'git') called at /kdesvn/src/extragear/utils/kdesrc-build/kdesrc-build line 6809
        main::__ANON__('Module=HASH(0x1f4e698)') called at /kdesvn/src/extragear/utils/kdesrc-build/kdesrc-build line 6855
        main::expandXMLModules('ksb::BuildContext=HASH(0x1f28200)', 'Module=HASH(0x1f4e698)') called at /kdesvn/src/extragear/utils/kdesrc-build/kdesrc-build line 8821
        eval {...} called at /kdesvn/src/extragear/utils/kdesrc-build/kdesrc-build line 8727
 at /home/kde-svn/perl5/perlbrew/perls/perl-blead/lib/site_perl/5.15.9/x86_64-linux/XML/Parser.pm line 192.
        XML::Parser::parse('XML::Parser=HASH(0x1c0b590)', 'GLOB(0x1f58c78)') called at /kdesvn/src/extragear/utils/kdesrc-build/kdesrc-build line 1364
        KDEXMLReader::getModulesForProject('KDEXMLReader=HASH(0x21822a0)', 'kde-workspace', 'git') called at /kdesvn/src/extragear/utils/kdesrc-build/kdesrc-build line 6809
        main::__ANON__('Module=HASH(0x1f4e698)') called at /kdesvn/src/extragear/utils/kdesrc-build/kdesrc-build line 6855
        main::expandXMLModules('ksb::BuildContext=HASH(0x1f28200)', 'Module=HASH(0x1f4e698)') called at /kdesvn/src/extragear/utils/kdesrc-build/kdesrc-build line 8821
        eval {...} called at /kdesvn/src/extragear/utils/kdesrc-build/kdesrc-build line 8727

Please submit a bug against kdesrc-build on http://bugs.kde.org/
------

There's no reason for a screenful of error output. We just need to state that kde-projects database is temporarily unavailable, perhaps mention bug reporting and/or sysadmin support.