How about this?
<a href="tel:..." onclick='return true'>Call me</a>
^^^^^^^^^^^^^
Tested example
<html>
<body>
<a href="http://www.yahoo.com" onclick="return true;">Yahoo (Working)</a>
<br />
<a href="http://www.yahoo.com" onclick="return false;">Yahoo (Not Working)</a>
</body>
</html>