After EBS 11.5.10 to R12.1.3 productin upgrade , workflow mails are not going out.

Workflow mailer is up and running .   But none of the mails are being sent out.

WE have following error in log files

.214.75-1:1:20420:SYSADMIN(0):-1:Thread[outboundThreadGroup1,5,outboundThreadGroup]:192.168.214.75:94927:1350333103289:11:ERROR:[SVC-GSM-WFMLRSVC-255273-10060 : oracle.apps.fnd.wf.mailer.SMTPMessageHandler.prepareMessages(String)]:Problem getting HTML content -> oracle.apps.fnd.wf.mailer.FormatterException: Problem getting the HTML content -> oracle.apps.fnd.wf.mailer.NotificationFormatter$FormatterSAXException: Problem obtaining the HTML content -> oracle.apps.fnd.wf.common.HTTPClientException: Unable to invoke method HTTPClient.HTTPResponse.listHeaders caused by: java.net.SocketTimeoutException: Read timed out
        at oracle.apps.fnd.wf.mailer.NotificationFormatter.handleResEndTag(NotificationFormatter.java:3461)
        at oracle.apps.fnd.wf.mailer.NotificationFormatter.endElement(NotificationFormatter.java:578)