Vim and matchadd compatibility don't work the same

I am playing around with the match functionality in vim (7.4) and I see some differences between match and matchadd that I cannot figure out.

The pattern I am using is simple to match some text in a specific row and column.

if i try the following it works and highlights the text:

:match Test /\%2l\%>4v\%<7v/

      

        
        
        
      

    

If I try the following it won't:

:call matchadd('Test','/\%2l\%>4v\%<7v/') 

      

        
        
        
      

    

'Test' is any selection group.

a simpler template, however, works fine, for example:

:call matchadd('Test','test') 

      

        
        
        
      

    

Any explanation or help would be helpful.