diff --git a/quickfixj-core/src/main/java/quickfix/SLF4JLog.java b/quickfixj-core/src/main/java/quickfix/SLF4JLog.java
index 58c1a07984..9ea40ccd71 100644
--- a/quickfixj-core/src/main/java/quickfix/SLF4JLog.java
+++ b/quickfixj-core/src/main/java/quickfix/SLF4JLog.java
@@ -62,9 +62,9 @@ public SLF4JLog(SessionID sessionID, String eventCategory, String errorEventCate
     }
 
     private Logger getLogger(SessionID sessionID, String category, String defaultCategory, String logPrefix) {
-        return LoggerFactory.getLogger((category != null
+        return LoggerFactory.getLogger(logPrefix + (category != null
                 ? substituteVariables(sessionID, category)
-                : defaultCategory) + logPrefix);
+                : defaultCategory));
     }
 
     private static final String FIX_MAJOR_VERSION_VAR = "\\$\\{fixMajorVersion}";
diff --git a/quickfixj-core/src/test/java/quickfix/SLF4JLogTest.java b/quickfixj-core/src/test/java/quickfix/SLF4JLogTest.java
index d3bc9e4827..3f903407bf 100644
--- a/quickfixj-core/src/test/java/quickfix/SLF4JLogTest.java
+++ b/quickfixj-core/src/test/java/quickfix/SLF4JLogTest.java
@@ -194,13 +194,13 @@ private void assertMessageLogged(SessionID sessionID, String categoryName, Strin
             // The conditional is required because of a bug in SLF4J 1.0
             // when used with JDK 1.4 logging. The wrapper does not pass
             // the logger name.
-            assertEquals(categoryName + sessionID + ": ", r.getLoggerName());
+            assertEquals(sessionID + ": " + categoryName, r.getLoggerName());
         }
         assertEquals(message, r.getMessage());
     }
 
     private TestHandler getTestHandler(String categoryName, SessionID sessionID) {
-        final Logger logger = Logger.getLogger(categoryName + sessionID + ": ");
+        final Logger logger = Logger.getLogger(sessionID + ": " + categoryName);
         TestHandler testHandler = null;
         final Handler[] handlers = logger.getHandlers();
         for (final Handler handler : handlers) {
@@ -214,7 +214,7 @@ private TestHandler getTestHandler(String categoryName, SessionID sessionID) {
     }
 
     private TestHandler setUpLoggerForTest(String category, SessionID sessionID) {
-        final Logger logger = Logger.getLogger(category + sessionID + ": ");
+        final Logger logger = Logger.getLogger(sessionID + ": " + category);
         logger.setUseParentHandlers(false);
         final Handler[] handlers = logger.getHandlers();
         for (final Handler handler : handlers) {