The benefits and tax systems are suffering lengthy downtime for upgrade work this week and over the weekend.

Our tipster says some of the work hasn't gone very well, specifically in relation to changes to Cisco gear.

"HMRC have planned upgrades to several of our IT systems to reflect process and legislative changes to the taxation system, which is due to start this week and will continue over the weekend," a government spokesman said today.

"We are also scheduled to upgrade other HMRC systems over the weekend. Anyone calling contact centres will hear a message explaining the situation, however, we apologise for the inconvenience caused."

The systems have been up and down since Tuesday. ®

Related stories

• Rev slammed for PAYE failure (2 February 2011)
• Ombudsman slams DWP, HMRC data dumbnesses (12 January 2011)
• HMRC spent £765m through Aspire last year (9 November 2010)
• UK gov could not procure its way out of a paper bag (11 October 2010)
• Opinion Disability rights activist chains self to tax office desk (22 September 2010)
• Taxman rejects 'lie detector' tech (20 September 2010)
• HMRC issues CD-rom alert to employers (2 September 2010)
• HMRC staff fired for racism over benefits (18 August 2010)
• Carousel fraudsters must pay back £92m (8 July 2010)
• HMRC mails wrong private info to 50,000 taxpayers (27 May 2010)
• Chips-for-gold fraud gang get 74 years' jail (25 May 2010)