Exclude and Include folders

[jhoomsharabi]

I want to include and exclude folders from directory listing, say I have  
following folders:
Abc/workspace
Def/workspace
Ghi/workspace
Jkl/workspace
Mno/workspace
 
And so on
I want to generate a tar file for the above folders but wants to exclude all 
“workspace” folders, I tried like this:
 
<tar destfile="archive_${KILLME}.tar" >
            <tarfileset dir="${base.dir}">
                <filename name="jobs/"/>
                <not>
                   <filename name="jobs/**/workspace/"/>
                </not>
            </tarfileset>
        </tar>
 
But it takes forever to generate tar file because each of “workspace” directory 
conatins huge data and these are the folders I want to exclude in my tar file.
Any idea where I am wrong or any thoughts should I do to resolve this issue.