The solution is a bit hacky right now, but at least it is a solution. Other Tier-2 users might be interested in this though. What you need to do is the following two steps:

1. Check out and setup your CMSSW area:

   scramv1 project CMSSW CMSSW_0_6_0
   cd CMSSW_0_6_0/src
   cvs co WhateverPackageYouWantToCompile
   

2. Then you need to replace a magic file used by SCRAM. Replace the file in your CMSSW_0_6_0/config/BuildFile with the stuff below:

   # -*-toolbox-*-
   
   CXXFLAGS := -m32 -Wa,--32 -pthread
   LDFLAGS:=-m32
   MODULEFLAGS:=-m32
   CSharedFlags:=-m32
   CXXSharedFlags:=-m32 -Wa,--32 -pthread
   
   <Architecture name=slc3_ia32_gcc323>
   <Flags CXXFLAGS="-m32 -Wa,--32 -pthread">
   <Flags LDFLAGS="-m32">
   <Flags MODULEFLAGS="-m32">
   <Flags CSharedFlags="-m32">
   <Flags CXXSharedFlags="-m32 -Wa,--32 -pthread">
   <Flags CXXSHAREDOBJECTFLAGS="-m32 -Wa,--32 -pthread">
   <makefile>
   F77compiler:=g77
   CCcompiler:=gcc3
   CXXFLAGS:=-m32
   LDFLAGS:=-m32
   MODULEFLAGS:=-m32
   CSharedFlags:=-m32
   CXXSharedFlags:=-m32
   </makefile>
   </Architecture>
   
   <Architecture name=slc3_amd64_gcc323>
   <makefile>
   F77compiler:=g77
   CCcompiler:=gcc3
   CXXFLAGS:=-m32
   LDFLAGS:=-m32
   MODULEFLAGS:=-m32
   CSharedFlags:=-m32
   CXXSharedFlags:=-m32
   </makefile>
   </Architecture>
   
   <Architecture name=slc3_ia32_gcc323_dbg>
   <Flags CXXFLAGS="-O0 -g -DDEBUG">
   <makefile>
   F77compiler:=g77
   CCcompiler:=gcc3
   CXXFLAGS:=$(patsubst -O2,,$(CXXFLAGS))
   CXXFLAGS:=-m32
   LDFLAGS:=-m32
   MODULEFLAGS:=-m32
   CSharedFlags:=-m32
   CXXSharedFlags:=-m32
   </makefile>
   </Architecture>
   
   <Architecture name=slc3_ia32_gcc344>
   <makefile>
   F77compiler:=g77
   CCcompiler:=gcc3
   </makefile>
   </Architecture>
   
   <Architecture name=slc3_ia32_gcc344_dbg>
   <Flags CXXFLAGS="-O0 -g -DDEBUG">
   <makefile>
   F77compiler:=g77
   CCcompiler:=gcc3
   CXXFLAGS := $(patsubst -O2,,$(CXXFLAGS))
   </makefile>
   </Architecture>
   
   # Storage locations:
   <ProductStore name=lib type=arch swap=true>
   <ProductStore name=bin type=arch swap=true>
   <ProductStore name=test type=arch swap=true>
   <ProductStore name=logs type=arch swap=true>
   <ProductStore name=doc>
   <ProductStore name=module type=arch swap=true>
   
   # ClassPaths:
   <ClassPath path=+Project/+SubSystem/+Package/scripts+scripts>
   <ClassPath path=+Project/Documentation+Documentation/+doc>
   <ClassPath path=+Project/+SubSystem/+Package/src+library>
   <ClassPath path=+Project/+SubSystem/+Package/bin+binary>
   <ClassPath path=+Project/+SubSystem/+Package/test+test>
   <ClassPath path=+Project/+SubSystem/+Package/data+data_install>
   
   # Add use for SCRAM-managed projects we're going to use 
   # (this ensures that we end up with LIBDIR and INCLUDE from each):
   <use name=lcgaa>
   <use name=coral>
   <use name=pool>
   <use name=seal>
   
   # Choose a compiler:
   <use name=cxxcompiler>
   

3. Then you need to tell SCRAM to reset its caches and compile your code:

   cd ~/CMSSW_0_6_0/src
   scramv1 b -r