[TYPO3-english] wfqbe: typolink with condition

[Claudio Strizzolo]

Hi all,
I have a question about configuring the wfqbe extension, in particular 
about handling a field that contains a file name.
In a database table handled through wfqbe I have an optional field 
containing the name of a pdf file. I'd like to render this field in the 
output as a link to the pdf file, if defined, or an empty space if not.
Up to now I have the following TS setup:

plugin.tx_wfqbe_pi1.customProcess.44 {  
  5 = TEXT
  5.value=Datasheet
  5.typolink {
    parameter=/path-to-where-pdfs-are-stored/###WFQBE_FIELD_5###
  }
}

If the pdf file has been defined, the link is correct, i.e.:

<a href="/path-to-where-pdfs-are-stored/myfile.pdf">Datasheet</a>

However, if the table field is empty, the following is displayed:

<a href="/path-to-where-pdfs-are-stored/">Datasheet</a>

The question is: how can I set up a condition in order to avoid 
displaying the above in case the file has not been defined?
Or is there any better way to handle the above in a totally different way?
Thanks in advance,

Claudio