SAP memory, SMO, singleton classes related to each user's activity

Hi all gurus,

facing a challenging task and would like to ask you for some clarifications...

In short; an user has to select a value from a WD custom popup. This value should then be retrieved in a standard method (by enhancing it) that follows in the process flow.

The problem is that between the popup and the method, a new user session is started ( the process I'm talking about is the creation of a shopping cart in SRM).

So:

- 1 - i tried to create a singleton class with GET & SET methods... but this is not working, as after the SET , a new user session starts and the previous singleton class instance is lost;

- 2 - I tried to "convert" the above class into a Shared Memory Area enabled one... defining the binding at Application Server level, it works. In the method in which I have to get the value, that is correctly retrieved.

But SMO seems not to fit with my requirement, as it's not user-specific. To better understand the issue, think about two users, say A and B, which are both processing that execution flow. Considering the following sequence:

1. user A selects a value (say "foo") from the popup; this is stored in SMA.
2. user B selects a different value (say "bar") from the same popup just a second after user A; this value OVERRIDES the previous one stored in SMA, as SMA is not user-specific!
3. As a result, when the execution flow for user A reaches the method in which the value is retrieved... the resulting value will be "bar", and not "foo".

I then read about SAP Memory which seems to be:

- user-specific;

- usable on multiple sessions from the same user.

I then tried as follows: when I have to set the value, I used the following instruction:

EXPORT proctype from proctype TO MEMORY ID 'ZPROCTYPE'.

where obviously proctype variable contains the user selection.

In the method, I used the following statement:

IMPORT proctype TO proctype  FROM MEMORY ID 'ZPROCTYPE'.

and, as in the case -1- of the singleton class, I get an empty value. Please notice that if I try to get the value BEFORE the new session is started, I can retrieve it correctly.

What am I missing? Does SAP Memory guarantee communication between multiple sessions started by the same user?

Any help will be highly appreciated ... as the question is quite urgent.

Thanks in advance