Fix in MySQLiStatement.mapPlaceholders() Use strictly placeholder names started with A-z symbol.

model/MySQLiStatement.php

@@ -38,7 +38,7 @@ class MySQLiStatement extends DbStatement
     protected function mapPlaceholders()
     {
         $matches = array();
-        if(preg_match_all('/(\?|:[A-z0-9_]+)/u', $this->request, $matches, PREG_OFFSET_CAPTURE)) {
+        if(preg_match_all('/(\?|:[A-z][A-z0-9_]*+)/u', $this->request, $matches, PREG_OFFSET_CAPTURE)) {
             $noname = 0;
             foreach ($matches[0] as $id=>$match) {
                 $match[2] = $matches[1][$id][0];