What size, in pixels, before resampling is the digital image, and from what camera?
How is it being printed, wet processed photo paper or offset lithograph?
What software do you have?
I have printed dozens of 50x75 cm. prints from 8/10 MP and 21 MP images and in none of them can you see pixels. From more than a meter distance you can't see much difference between them. From 30 cm you can see much more detail in the prints from the 5D2, despite the fact that the cameras had much the same sensor resolution. From the 5D2 I have also made flawless 67x100 cm. prints.