Standard & Poor's Ratings Services last week dealt Sun Microsystems a blow by cutting its corporate credit rating to junk status. In a research note, the credit rating company warned that Sun will have trouble boosting revenue in the near-term and that it faces tougher competition that ever before in the server market. "The downgrade reflects weak and inconsistent profitability, and our expectation that Sun will be challenged to profitably expand its market presence," said Standard & Poor's credit analyst Martha Toll-Reed. Word of the cut appeared to hurt Sun shares, during Friday's trading. After enjoying a recent run to more than $5 per share, Sun's stock dropped seven per cent on Friday to $4.80. Sun has close to $1.3bn in outstanding debt but also boasts more than $5bn in cash. The move was a surprise to some analysts who noted that Sun appears to have put the worst behind it.