After upgrading to RHEL4, the program gnomecal was no longer present. The newer program was evolution, but it would not import the user-cal.vcf file from gnomecal. The solution was to install Sunbird (Mozilla’s calendar) and import the data there. Unfortunately, a direct import didn’t work. First the file user-cal.vcf was renamed to user-cal.vcs. This was then imported into Outlook. In Outlook, the calendar was then exported as a comma-separated file, which could successfully be imported into Sunbird.