Index: src/com/mysql/jdbc/ResultSetImpl.java
===================================================================
--- src/com/mysql/jdbc/ResultSetImpl.java	(revision 6806)
+++ src/com/mysql/jdbc/ResultSetImpl.java	(working copy)
@@ -235,6 +235,8 @@
 
 	protected Map columnNameToIndex = null;
 	
+	protected Map columnToIndexCache = null;
+
 	protected boolean hasBuiltIndexMapping = false;
 
 	/**
@@ -718,6 +720,7 @@
 		this.fullColumnNameToIndex = new TreeMap(String.CASE_INSENSITIVE_ORDER);
 		this.columnNameToIndex = new TreeMap(String.CASE_INSENSITIVE_ORDER);
 		
+		this.columnToIndexCache = new HashMap(numFields);
 		
 		// We do this in reverse order, so that the 'first' column
 		// with a given name ends up as the final mapping in the
@@ -1093,6 +1096,12 @@
 			buildIndexMapping();
 		}
 
+		index = (Integer) this.columnToIndexCache.get(columnName);
+		
+		if (index != null) {
+			return index.intValue() + 1;
+		}
+		
 		index = (Integer) this.columnLabelToIndex.get(columnName);
 
 		if (index == null && this.useColumnNamesInFindColumn) {
@@ -1104,6 +1113,7 @@
 		}
 		
 		if (index != null) {
+			this.columnToIndexCache.put(columnName, index);
 			return index.intValue() + 1;
 		}