pkg/40370: mono-xsp build problem on Linux

[pkgsrc%blackmouse.biz@localhost]

>Number:         40370
>Category:       pkg
>Synopsis:       mono-xsp build problem on Linux
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Jan 11 13:35:00 +0000 2009
>Originator:     Ondrej Tuma
>Release:        current
>Organization:
Blackmouse
>Environment:
Linux vs284 2.6.16.28-xen #1 SMP Fri Oct 13 16:20:48 CEST 2006 x86_64 GNU/Linux
>Description:
make[2]: Entering directory `/usr/pkgsrc/www/mono-xsp/work/xsp-2.0/test'
/usr/pkg/bin/mcs -pkg:dotnet -r:System.Xml.dll -target:library 
-out:SiteMapReader_1.1.dll SiteMapReader_1.1.cs
error CS0006: cannot find metadata file 
`System.Runtime.Serialization.Formatters.Soap.dll'
Compilation failed: 1 error(s), 0 warnings
make[2]: *** [SiteMapReader_1.1.dll] Error 1

full log is here: 
http://download.blackmouse.biz/blackmouse-current/x86_64/pkgstat/20090111.1344/www/mono-xsp/.broken.html

I thing, that this error i got on i686 machine too, but I'm not sure.
>How-To-Repeat:
bmake
>Fix: