Multiple prompts for same variable on workbook with 2 queries

Hi Experts

I'm searched high and low for this answer before posting but cannot find the answer to my specific problem.

I have a 3.x workbook which contains 2 queries on 2 separate sheets.

In each query, I have a variable to select a date range.  The same variable is used in each query which is held against the same InfoObject.

For some reason, I cannot get the query to prompt only once for the variable value.  Instead, it prompts, refreshes the query and then prompts for the 2nd.

I know there is a feature in v7 to tie these together but am I missing something with what I am going in my 3.x workbook ?

Settings in each query are set to:

'Enable Interactive Functions'

'Refresh query when opening workbook'

Hope you can help

Thanks

Ian