data0type.ic:

  Change the sorting order of TEXT columns in InnoDB: pad with spaces at the end in comparisons; we MUST UPDATE the MySQL MANUAL to warn about the need to rebuild tables (also MyISAM) in certain cases in an upgrade to 5.0.3; TODO: study what complications the missing DATA_BINARY_TYPE flag in InnoDB < 4.0.14 causes: we would compare then also BLOBs with space padding, not just TEXT

innobase/include/data0type.ic

@@ -195,10 +195,12 @@ dtype_get_pad_char(
 	    || type->mtype == DATA_BINARY
 	    || type->mtype == DATA_FIXBINARY
 	    || type->mtype == DATA_MYSQL
-	    || type->mtype == DATA_VARMYSQL) {
+	    || type->mtype == DATA_VARMYSQL
+	    || (type->mtype == DATA_BLOB
+		&& (type->prtype & DATA_BINARY_TYPE) == 0)) {
 
 		/* Space is the padding character for all char and binary
-	        strings */
+	        strings, and starting from 5.0.3, also for TEXT strings. */
 
 		return((ulint)' ');
 	}