diff --git a/src/sbbs3/ctrl/sbbsctrl.bpr b/src/sbbs3/ctrl/sbbsctrl.bpr
index cff30219225f5a53b84b72b90473c566202f8a58..9086fbd03dc0e029038b71b2bd7d60e770380c90 100644
--- a/src/sbbs3/ctrl/sbbsctrl.bpr
+++ b/src/sbbs3/ctrl/sbbsctrl.bpr
@@ -47,7 +47,7 @@
     <DEBUGLIBPATH value="$(BCB)\lib\debug"/>
     <RELEASELIBPATH value="$(BCB)\lib\release"/>
     <LINKER value="ilink32"/>
-    <USERDEFINES value="SBBS;_DEBUG;RINGBUF_SEM"/>
+    <USERDEFINES value="SBBS;_DEBUG;RINGBUF_SEM;RINGBUF_MUTEX"/>
     <SYSDEFINES value="NO_STRICT;_VIS_NOLIB"/>
     <MAINSOURCE value="sbbsctrl.cpp"/>
     <INCLUDEPATH value="..\;..;C:\Borland\CBuilder6\Projects;..\..\xpdev;..\..\smblib;$(BCB)\include;$(BCB)\include\vcl"/>
@@ -59,7 +59,7 @@
   <OPTIONS>
     <IDLCFLAGS value="-I..\. -I.. -IC:\Borland\CBuilder6\Projects -I..\..\xpdev -I..\..\smblib 
       -I$(BCB)\include -I$(BCB)\include\vcl -src_suffix cpp -DSBBS -D_DEBUG 
-      -DRINGBUF_SEM -boa"/>
+      -DRINGBUF_SEM -DRINGBUF_MUTEX -boa"/>
     <CFLAG1 value="-Od -H=c:\borland\CBUILD~2\lib\vcl60.csm -Hc -Vx -Ve -X- -r- -a8 -b- -k -y 
       -v -vi- -c -tW -tWM"/>
     <PFLAGS value="-$Y+ -$W -$O- -$A8 -v -JPHNE -M"/>
@@ -209,12 +209,13 @@ Item0=$(BCB)\source\vcl;C:\src\xpdev\
 Item1=$(BCB)\source\vcl
 
 [HistoryLists\hlConditionals]
-Count=5
-Item0=SBBS;_DEBUG;RINGBUF_SEM
-Item1=SBBS;_DEBUG
-Item2=SBBS
-Item3=SBBS;SMB_GETMSGTXT;_DEBUG
-Item4=SBBS;SMB_GETMSGTXT
+Count=6
+Item0=SBBS;_DEBUG;RINGBUF_SEM;RINGBUF_MUTEX
+Item1=SBBS;_DEBUG;RINGBUF_SEM
+Item2=SBBS;_DEBUG
+Item3=SBBS
+Item4=SBBS;SMB_GETMSGTXT;_DEBUG
+Item5=SBBS;SMB_GETMSGTXT
 
 [Debugging]
 DebugSourceDirs=$(BCB)\source\vcl;C:\src\xpdev\