So I have a MAC BOOK PRO, running Lion. Here is the situation; I attempted to split the single main partition by creating a newer smaller one which was initially planned to support 20GB. I accidentally split the main partition in half; and ignorantly tried to prevent the completion of said task by interrupting the process. It is only after I had forcefully closed the Disk Utility app, that I had realized that my partition displayed itself as officially full. I am now unable to split partitions.