I've seen one question posted over and over since CorelDRAW X5 was released. Users who have always gotten solid black on their output are now getting gray instead and they are frustrated. I won't try to explain why it is happening as it gets into color management details. The key is that it can easily be solved with a single click. Go into the default color management settings (or the document settings for files that were already created in CorelDRAW X5) and check the Preserve Pure Black checkbox. Now the black will output as black.
Now I'll put in a shameless plug as the answer is available. If you simple want to understand how to use the color management in CorelDRAW X5, you can get Lesson 12 of CorelDRAW X5 Unleashed
and it will help you set up color management. Better yet, get the entire CorelDRAW X5 Unleashed Training DVD
and it will answer thousands of your CorelDRAW questions.