Dell Inc. customers who ordered its new high-end XPS M1330 notebook shortly after it launched in late June are hopping mad after the computer maker has pushed out delivery dates several times and canceled orders without notification.

A Dell executive said this weekend that the laptop is now shipping in limited quantities but warned buyers to expect additional delays.

The M1330, which Dell has promoted since the ultralight portable’s in August, apparently — both for those who had already ordered and for customers currently placing orders.

But as shipping status updates on the Dell site didn’t change and follow-on e-mails arrived with even later delivery dates, customers began fuming.

“My delivery date was changed today. … They added another 20 days,” said “Patrick J” on July 13 in a posting to Dell2Dell. “I ordered mine the 26th june and will not get it until the 14th of august.”

“Ordered a XPS M1330 on June 29th,” said another customer, identified only as Brian. “The shipping date (July 16th) was modified twice (Aug 7th and then Sept 13th!!!) I sold my old laptop. I’m without a pc since two weeks. I had to wait 5 more. I’m happy.”

Other people who had placed orders reported Dell had canceled them without their approval or notice. “On Friday the 20th I received a call from another person at Dell stating that (all?) orders for XPS M1330 computers had been accidentally canceled due to invalid system configuration errors,” said Clinton Begin on July 21. ” So what’s the deal Dell? Is my machine in the mail set to arrive on Monday? Or is it MIA? How can your systems be screwed up so bad? The left hand clearly doesn’t know what the right is doing.”

Also on July 20, Lionel Menchaca, Dell’s digital media manager and the company’s regular blogger on Dell2Dell, said M1330 notebooks had begun shipping but that “the process to ramp production has taken a bit longer than we expected.” He laid the blame on one or more unspecified components. “The reality is that due to the unique nature of some features of the notebook, we’ve had to work through some additional manufacturing processes.” He also claimed then that customers placing new orders would see a ship date approximately four weeks in the future.