One year after IBM launched its free productivity suite, users can for the first time import files saved in Microsoft Office 2007's native Office Open XML (OOXML) document format.

The update means that Lotus Symphony 1.3 could remove a worry for those considering dropping Microsoft Office.

The move also brings Symphony up to par with, the open-source suite it is based on. 3.0, released last Autumn, which lets users import OOXML documents.

But like Symphony, cannot save documents in OOXML, the controversial document format created, publicly released by Microsoft and made an international standard last year.

Last year, IBM said it would provide unlimited remote support for up to 20,000 Symphony users for a flat fee of $25,000 (£15,390) a year.

By comparison, an enterprise agreement to licence Office for the same number of users would cost $3.1 million (£1.9 million) a year, before any discounts.

Companies already paying for Lotus Notes 8 or Lotus Foundations, IBM's server software bundle for smaller firms, can get free support for Symphony, says IBM.

An IBM spokesman declined to say how many users it has for Symphony.

"We continue to see very strong interest and use [among firms using Notes or Foundations,]" he said in an email. "In a recent survey of Notes customers, [approximately] 25 percent of them are either evaluating or deploying Lotus Symphony."

Symphony now limits users to saving files into Office 2003 or Office 2000's document formats. But the spokesman said saving in Office 2007 format was not off the table. "We will continue to monitor the demand for this function and based on that demand respond as needed," he said.