added LIKE condition escaping to all drivers and Active Record
updated all DB drivers to accept arrays in escape_str()
diff --git a/system/database/DB_active_rec.php b/system/database/DB_active_rec.php
index c757e6a..d48f43e 100644
--- a/system/database/DB_active_rec.php
+++ b/system/database/DB_active_rec.php
@@ -707,7 +707,7 @@
 
 			$prefix = (count($this->ar_like) == 0) ? '' : $type;
 
-			$v = $this->escape_str($v);
+			$v = $this->escape_like_str($v);
 
 			if ($side == 'before')
 			{
@@ -722,6 +722,12 @@
 				$like_statement = $prefix." $k $not LIKE '%{$v}%'";
 			}
 			
+			// some platforms require an escape sequence definition for LIKE wildcards
+			if ($this->_like_escape_str != '')
+			{
+				$like_statement = $like_statement.sprintf($this->_like_escape_str, $this->_like_escape_char);
+			}
+			
 			$this->ar_like[] = $like_statement;
 			if ($this->ar_caching === TRUE)
 			{