If you have a look in the list of extension that you can find in the download section or in the JMS tools help button, you can see that we have not yet reviewed this JSeblod extension.
www.jms2win.com/component/content/article/135
So we can not tell you why you have this error.
How have you installed this extension in the slave site ?
Did you re-install it in the back-end of the slave site ?
Have you received an error during its re-install ?
If you want that we review this exention to add its definition in the JMS tools, send us this extension in attachement of an email. (see contact us for the email)