Cisco has been unable to meet Apple's deadline for making its virtual private network (VPN) client work with Mac OS X Tiger.

Cisco spokeswoman Mojgan Khalili told Cnet that although the networking company had been working with Apple to provide VPN support, it had been unable to get things completed in time for today's release.

"Support will be available sometime in May," she said.

The delay will hit corporate Mac users who use Cisco's VPN technology to encrypt traffic, so that files can be securely accessed on corporate networks, suggests Cnet.