--- src/com/mysql/jdbc/PreparedStatement.java
+++ src/com/mysql/jdbc/PreparedStatement.java
@@ -181,7 +181,9 @@
 
 		byte[][] staticSql = null;
 
-		boolean isOnDuplicateKeyUpdate = false;
+        int onDuplicateKeyUpdateIndex = -1;
+        
+        boolean isOnDuplicateKeyUpdateWithArgs = false;
 		
 		/**
 		 * Represents the "parsed" state of a client-side
@@ -199,7 +201,8 @@
 							SQLError.SQL_STATE_ILLEGAL_ARGUMENT);
 				}
 
-				this.isOnDuplicateKeyUpdate = containsOnDuplicateKeyInString(sql);
+                this.onDuplicateKeyUpdateIndex = containsOnDuplicateKeyInString(sql);
+                this.isOnDuplicateKeyUpdateWithArgs = this.onDuplicateKeyUpdateIndex == -1;
 				
 				this.lastUsed = System.currentTimeMillis();
 
@@ -321,6 +324,11 @@
 					if ((c == '?') && !inQuotes && !inQuotedId) {
 						endpointList.add(new int[] { lastParmEnd, i });
 						lastParmEnd = i + 1;
+                        if (!this.isOnDuplicateKeyUpdateWithArgs //if false there are a on duplicate key information.
+                                                                 // or there are already set to true by this check.
+                             && i > this.onDuplicateKeyUpdateIndex ) {
+                            this.isOnDuplicateKeyUpdateWithArgs = true;
+                        }
 					}
 
 					if (!inQuotes && (i < stopLookingForLimitClause)) {
@@ -1127,7 +1135,7 @@
 			this.canRewrite = StringUtils.startsWithIgnoreCaseAndWs(
 					this.originalSql, "INSERT", this.statementAfterCommentsPos) 
 			&& StringUtils.indexOfIgnoreCaseRespectMarker(this.statementAfterCommentsPos, this.originalSql, "SELECT", "\"'`", "\"'`", false) == -1 
-			&& !containsOnDuplicateKeyUpdateInSQL();
+            && ( !containsOnDuplicateKeyUpdateInSQL() || !containsOnDuplicateKeyUpdateInSQLWithArgs());
 			
 			this.hasCheckedForRewrite = true;
 		}
@@ -2081,7 +2089,15 @@
 	}
 
 	protected boolean containsOnDuplicateKeyUpdateInSQL() {
-		return this.parseInfo.isOnDuplicateKeyUpdate;
+        return this.parseInfo.onDuplicateKeyUpdateIndex != -1;
+    }
+    
+    protected int indexOfOnDuplicateKeyUpdateInSQL() {
+        return this.parseInfo.onDuplicateKeyUpdateIndex;
+    }
+    
+    protected boolean containsOnDuplicateKeyUpdateInSQLWithArgs() {
+        return this.parseInfo.isOnDuplicateKeyUpdateWithArgs;
 	}
 
 	private String extractValuesClause() throws SQLException {
@@ -2112,7 +2128,9 @@
 				return null;
 			}
 	
-			int indexOfLastParen = this.originalSql.lastIndexOf(')');
+            int indexOfLastParen = (containsOnDuplicateKeyUpdateInSQL() && !containsOnDuplicateKeyUpdateInSQLWithArgs()) ?
+                                                     this.originalSql.lastIndexOf(')', (indexOfOnDuplicateKeyUpdateInSQL()))
+                                                     : this.originalSql.lastIndexOf(')');
 	
 			if (indexOfLastParen == -1) {
 				return null;
@@ -2238,12 +2256,19 @@
 				+ (numBatches * (valuesClause.length() + 1)));
 
 		newStatementSql.append(this.originalSql);
+        if ((containsOnDuplicateKeyUpdateInSQL() && !containsOnDuplicateKeyUpdateInSQLWithArgs())) {
+            newStatementSql.setLength(indexOfOnDuplicateKeyUpdateInSQL() + 1);
+        }
 
 		for (int i = 0; i < numBatches - 1; i++) {
 			newStatementSql.append(',');
 			newStatementSql.append(valuesClause);
 		}
 
+        if ((containsOnDuplicateKeyUpdateInSQL() && !containsOnDuplicateKeyUpdateInSQLWithArgs())) {
+            newStatementSql.append(this.originalSql.substring(indexOfOnDuplicateKeyUpdateInSQL()));
+        }
+        
 		return newStatementSql.toString();
 	}
 
@@ -5189,8 +5214,8 @@
 		return count;
 	}
 	
-	protected boolean containsOnDuplicateKeyInString(String sql) {
+    protected int containsOnDuplicateKeyInString(String sql) {
 		return StringUtils.indexOfIgnoreCaseRespectMarker(0, 
-				sql, " ON DUPLICATE KEY UPDATE ", "\"'`", "\"'`", !this.connection.isNoBackslashEscapesSet()) != -1;
+       sql, " ON DUPLICATE KEY UPDATE ", "\"'`", "\"'`", !this.connection.isNoBackslashEscapesSet());
 	}
 }
--- src/com/mysql/jdbc/ServerPreparedStatement.java
+++ src/com/mysql/jdbc/ServerPreparedStatement.java
@@ -266,7 +266,7 @@
 	 */
 	private static final byte MAX_TIME_REP_LENGTH = 13;
 	
-	private boolean hasOnDuplicateKeyUpdate = false;
+	private int hasOnDuplicateKeyUpdate = -1;
 
 	private void storeTime(Buffer intoBuf, Time tm) throws SQLException {
 		
@@ -2897,6 +2897,14 @@
 	}
 
 	protected boolean containsOnDuplicateKeyUpdateInSQL() {
+		return this.hasOnDuplicateKeyUpdate != -1;
+	}
+	
+	protected int indexOfOnDuplicateKeyUpdateInSQL() {
 		return this.hasOnDuplicateKeyUpdate;
 	}
+    
+    protected boolean containsOnDuplicateKeyUpdateInSQLWithArgs() {
+        return true; //Return true to not parse the query 
+    }
 }
--- src/com/mysql/jdbc/StringUtils.java
+++ src/com/mysql/jdbc/StringUtils.java
@@ -1020,8 +1021,8 @@
 				contextMarker = c;
 			} else if (c == target.charAt(0) && !escaped
 					&& contextMarker == Character.MIN_VALUE) {
-				if (indexOfIgnoreCase(i, src, target) != -1)
+       if (startsWithIgnoreCase(src, i, target))
 			}
 		}