[Plugin: W3 Total Cache] error_log

Yesterday I updated w3 total cache plugin version 0.9.2.3 to 0.9.2.4. after update, automatically created some error log file as below

[26-Apr-2012 13:26:57] PHP Fatal error: Call to undefined function w3_url_format() in /public_html/wp-content/plugins/w3-total-cache/lib/W3/Plugin/PgCacheAdmin.php on line 213

Does anyone know what it means? any ideas on how to fix this problem?

https://www.ads-software.com/extend/plugins/w3-total-cache/