diff --git a/ChangeLog b/ChangeLog
index 61eb463b5..39f616753 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2011-08-01  Wolfgang Sourdeau  <wsourdeau@inverse.ca>
+
+	* OpenChange/MAPIStoreFSMessage.m
+	(-getAvailableProperties:inMemCtx:): take only NSNumber keys into
+	account.
+
 2011-07-29  Wolfgang Sourdeau  <wsourdeau@inverse.ca>
 
 	* OpenChange/MAPIStoreTable.m (-dealloc): free the list of
diff --git a/OpenChange/MAPIStoreFSMessage.m b/OpenChange/MAPIStoreFSMessage.m
index a67105a8f..03a4ffe64 100644
--- a/OpenChange/MAPIStoreFSMessage.m
+++ b/OpenChange/MAPIStoreFSMessage.m
@@ -23,6 +23,8 @@
 #import <Foundation/NSArray.h>
 #import <Foundation/NSData.h>
 #import <Foundation/NSDictionary.h>
+#import <Foundation/NSString.h>
+#import <Foundation/NSValue.h>
 
 #import "MAPIStoreContext.h"
 #import "MAPIStorePropertySelectors.h"
@@ -37,8 +39,15 @@
 #include <mapistore/mapistore.h>
 #include <mapistore/mapistore_errors.h>
 
+Class NSNumberK;
+
 @implementation MAPIStoreFSMessage
 
++ (void) initialize
+{
+  NSNumberK = [NSNumber class];
+}
+
 + (int) getAvailableProperties: (struct SPropTagArray **) propertiesP
                       inMemCtx: (TALLOC_CTX *) memCtx
 {
@@ -138,7 +147,7 @@
 //   return [NSNumber numberWithUnsignedInt: propTag];
 // #else
       key = [keys objectAtIndex: count];
-      if (![key isEqualToString: @"attachments"])
+      if ([key isKindOfClass: NSNumberK])
         {
 #if (GS_SIZEOF_LONG == 4)
           properties->aulPropTag[count] = [[keys objectAtIndex: count] unsignedLongValue];