According to a Wall Street Journal (WSJ) report, tech giant Apple has admitted that it is aware of an iMessage-related issue in the latest version of its iOS mobile operating system - the iOS 7.

The iOS7 glitch which has recently been acknowledged by Apple causes disruption to the delivery of iMessage texts. The iMessage feature of the iOS essentially unfolds the `free texting' advantage for the users of Apple devices. In addition, iMessage also converts the text messages into SMS texts for non-iOS users.

Hordes of infuriated iOS7 users - who have had problems in sending messages through iMessage - having complained about the glitch on the Twitter social media as well as on Apple's messages boards.

The most common complaint which has been reported by the iOS7 users in connection with the disrupted iMessage delivery is that while the messages appear to be sent, they later appear with a big red exclamation mark indicating that the delivery of the message had failed.

Acknowledging the glitch in iOS7's iMessage delivery mechanism, Apple has said that it is working on a fix to address the issue. Noting that the problem will be fixed in a forthcoming software update, Apple said in a statement: "In the meantime, we encourage any users having problems to reference our troubleshooting documents or contact AppleCare to help resolve their issue."