 | Baltimore Technologies' MailSecure |
| Celo Communications CeloCom Mail 1.5 |
| Citibank Global File Handler |
| Control Data Cipher*Mail 1.5 |
| Cyclone Software Interchange Server 2.0 |
| Entrust Technologies Entrust Express 4.0 |
| Frontier Technologies e-Lock 2.0 |
| Microsoft Outlook and Outlook Express |
| Labcal Technologies IsoShield/Mail |
| Microsoft Outlook Express 4.0 |
| Microsoft Outlook 98 Beta 2 |
| Mission Critical Clavis 0.1b |
| Netscape Communicator 4.01 |
| NEL Mahobin* |
