Hi Michaël, as you may have seen in my other message, I have created a
SqueakSource project which I believe has cleared up all the loading issues for
3.7 - 3.9.  Here's the http respository spec:

MCHttpRepository
    location: 'http://kilana.unibe.ch:8888/MaClientServer'
    user: ''
    password: ''

Then load "Ma client server tester" to get the framework and the test cases.

To run the tests: 

  MaClientServerTestCase kickoff

> I don't need it specifically. But I want to use the Object Request Layer and
> the connect method of MaTcpRequestServerLink do "serializer
> classDefinitionsByteArray: (idAndProtocol at: 2)" which performs "self
> classDefinitions: (self materializeGraph: aByteArray)".

Oops!  You are right, this method was miscategorized.  It is now included in
the SqueakSource version.

> Here is the code I used:
> server side:
> myServer := MaTcpRequestServer protocol:
> 	{ OrderedCollection.
> 	Dictionary. }.
> myServer
> 	processOn: 12345
> 	using: [ :requestByteArray | requestByteArray reverse ]
> 
> client side:
> myLinkToServer := MaTcpRequestServerLink
> 	hostAddress: #(127 0 0 1) asByteArray
> 	port: 12345.
> myLinkToServer connect.
> self submit: 'Hello!'

BTW, to see all the classes you *don't* need for your procotol, print:

  MaClassIdManager minimumClasses

Dictionary and OrderedCollection, among others, do not need to be specified.

> After several tests (and by taking your "serverTest.ws" as starting point)
> I've found that adding "myServer console: MaTranscriptConsole new." in the
> server resolved the problem. But I'm wondering why it fails with the default
> console (MaRequestServerConsole).

I made the test suite so that client1 uses a MaTranscriptConsole and client2
doesn't.  It seems to be working..

Thanks for your patience, let me know if you have questions or issues.

 - Chris