Just replace the rexxapitypes.h file with the one from main/branches/4.1/trunk/api/platform/windows/ in the repostory

That is what I would do.  It is the simplest.

This is what I did and it seems to work, no error messages. But suddenly I stumble over a new problem in the link of oosqlite.dll:

        link /nologo /SUBSYSTEM:Windows rexx.lib rexxapi.lib user32.lib advapi32.lib -def:src\platform\windows\ooSQLite.def /DLL build\release\sqlite3
.obj build\release\ooSQLite.obj build\release\APICommon.obj build\release\ooSqlSysLibrary.obj  build\release\nextchar.obj build\release\ieee754.obj bu
ild\release\percentile.obj build\release\rot13.obj  build\release\regexp.obj build\release\spellfix.obj build\release\wholenumber.obj -out:build\relea
LINK : fatal error LNK1181: cannot open input file 'build\release\sqlite3.obj'

The compile of sqlite3.c looks like this in my case:

$(OUT_DIR)\sqlite3.obj: src\sqlite\sqlite3_with_codec.c src\sqlite\sqlite3.h Makefile.win
  cl $(CFLAGS) /DOOSQLITE_BUILD /Fo.\$(OUT_DIR)\ src\sqlite\sqlite3_with_codec.c

This has worked for a long time but now suddenly sqlite3.obj can't be found. The above compile actually generates sqlite3_with_codec.obj now instead of sqlite3.obj and I cannot figure out why. Any idea?