Index: wp-admin/import/mt.php
===================================================================
--- wp-admin/import/mt.php	(revision 4261)
+++ wp-admin/import/mt.php	(working copy)
@@ -75,6 +75,7 @@
 
 	function get_entries() {
 		set_magic_quotes_runtime(0);
+		ini_set('memory_limit', '50M');
 		$importdata = file($this->file); // Read the file into an array
 		$importdata = implode('', $importdata); // squish it
 		$importdata = preg_replace("/(\r\n|\n|\r)/", "\n", $importdata);