[jssch]

Is there a free email client that will receive and send via imap that will also allow me to import an old pst file from Outlook 2003?

[cwwozniak]

Mozilla Thunderbird may work for you if you still have Outlook installed on the computer. According to a MozillaZine article, Thunderbird imports the PST file contents through calls to Outlook. The article also explains why you may find it difficult to find any program that can directly import a PST file's contents without using an installed copy of Outlook.