Sun Microsystems has posted a net loss of $34m for the third quarter, blaming "macroeconomic uncertainty" in the US.

The world's fourth-largest maker of servers registered revenues of $3.27bn for the period ending 30 March, a fall of 0.5 per cent compared to the same period last year.

"The US economy presented Sun with significant challenges in the third quarter," said chief executive Jonathan Schwartz in a statement.

Chief financial officer Michael Lehman warned that fourth-quarter sales would also be little changed, after previously predicting five per cent gains for the second half of the year.

Sun will be hoping that its $1bn acquisition of free-software maker MySQL in February will help bolster future revenue through software support and maintenance, as well as spurring server sales and storage to MySQL users.

Overall server shipments of 80,000 were up for the period, an increase of six per cent on the same quarter a year ago.