Research in Motion said the software upgrade for its PlayBook tablet has been delayed to February next year.

The tablet will ship without the BlackBerry Messenger software, the company said in a blog post on its site.

The PlayBook has been criticized because it cannot handle e-mail routed through its secure enterprise servers without being linked to a BlackBerry.

Earlier this month, RIM had said it plans to introduce the BBX operating software for the BlackBerry smartphone and PlayBook tablet, but did not say when the software would show up in a product.

(Reporting by Maneesha Tiwari in Bangalore)