0x8000FFFF access violation when disposing Redemption RdoMail object

Six of our 400+ users reported this error in the last two months:

System.Runtime.InteropServices.COMException (0x8000FFFF): Access violation at address 0000000000D7BA95 
in module 'Redemption64.dll. Read of address FFFFFFFFFFFFFFFF 
at System.IDisposable.Dispose()

This exception is raised just after a mail is saved on the user drive. The code that raises this exception is:

var msg = rdoMail as IDisposable;
if (msg != null)
   msg.Dispose();

Any idea why this error occurs once in a while?

Notes:

• Our Outlook 365 client version is "Product ID Version 2008 (Build 13127.20408 Click-to-Run Semi-Annual Entreprise Channel (Preview)"
• The Redemption64.dll file version: 5.18.0.5142.

This problem (64 bit specific) was fixed about a month ago after version 5.24 was released. Please send an email to redemption (at) dimastr (dot) com for an updated version.