Press Release

PalmSource Schedules First Quarter Fiscal Year 2005 Results & Conference Call For September 23, 2004

SUNNYVALE, Calif., September 7, 2004- PalmSource, Inc. (NASDAQ: PSRC) provider of Palm OS®, a leading operating system powering next generation mobile devices and smartphones, will release results for the first quarter of fiscal year 2005 results on Thursday, September 23, 2004 after market close. David Nagel, president & chief executive officer and Al Wood, chief financial officer, will discuss first quarter of fiscal year 2005 results and business outlook of the second quarter on a conference call scheduled for 5:00 PM Eastern Daylight Time / 2:00 PM Pacific Daylight Time that same day.

A live and archived Web cast of this call can be accessed at PalmSource's web site at http://www.palmsource.com/about/ir.html. The Web cast is also being distributed over CCBN's Investor Distribution Network to both institutional and individual investors through CCBN's individual investor center at www.companyboardroom.com and by visiting any of the investor sites in CCBN's Individual Investor Network or via CCBN's password-protected event management site, StreetEvents (www.streetevents.com).

About PalmSource
PalmSource, Inc. is the company behind Palm OS, a leading operating system powering mobile information devices. Approximately 35 million Palm Powered handhelds and smartphones have been sold to date worldwide. Industry leaders Aceeca, AlphaSmart, Fossil, Garmin, GSL, Kyocera, Lenovo, palmOne, QTech, Samsung, Sony, Symbol Technologies and Tapwave license Palm OS to create diverse mobile devices that meet unique customer needs. Palm OS has given rise to a large community of users, enterprises, developers and manufacturers, who together make up the Palm Powered Economy. More information about PalmSource is available at www.palmsource.com, www.palmsource.co.uk, www.palmsource.fr, www.palmsource.de and www.palmsource.com.cn.

Copyright ﾂｩ 2004, PalmSource, Inc. PalmSource and Palm OS are trademarks or registered trademarks of PalmSource, Inc. or its affiliate in the United States, France, Germany, Japan, the United Kingdom, and other countries. All other brands, product names, company names, trademarks and service marks are the properties of their respective owners. All rights reserved.