Index: wp-admin/includes/upgrade.php
===================================================================
--- wp-admin/includes/upgrade.php	(revision 17316)
+++ wp-admin/includes/upgrade.php	(working copy)
@@ -1508,6 +1508,7 @@
 						$keyname = $tableindex->Key_name;
 						$index_ary[$keyname]['columns'][] = array('fieldname' => $tableindex->Column_name, 'subpart' => $tableindex->Sub_part);
 						$index_ary[$keyname]['unique'] = ($tableindex->Non_unique == 0)?true:false;
+						$index_ary[$keyname]['index_type'] = $tableindex->Index_type;
 					}
 
 					// For each actual index in the index array
@@ -1519,6 +1520,9 @@
 						} else if($index_data['unique']) {
 							$index_string .= 'UNIQUE ';
 						}
+						if ( 'FULLTEXT' == strtoupper( $index_data['index_type'] ) ) {
+							$index_string .= 'FULLTEXT ';
+						}
 						$index_string .= 'KEY ';
 						if ($index_name != 'PRIMARY') {
 							$index_string .= $index_name;