Null value for Web Service task input

I'm attempting to use the Web Service task to call a method provided by a vendor. The inputs are all simple types so that helps a lot, but for one input it's a string array. If I enter a single string value for a given id using the array dialog, the method works fine.

However if I try to change the input to use a variable to provide the value it fails. I'm assuming that you can't create a variable to return a string array. Please let me know if this is the case or if I'm missing something obvious ;-)

In addition, is there a way to specify a null value for an input? Currently there doesn't appear to be a way to do this in SP2. I tried leaving the string empty which didn't work and I tried using a variable with expression "NULL(DT_WSTR, 1252)" but that failed too.

You should be able to store an array of strings in a variable typed as Object. Not sure how well that will pass to the web service though.|||

Thanks for your reply John. As you suggested, I changed the variable type to object and assigned a string array to it. I was skeptical that it would work, but when I used that in the Web Service it worked! So many thanks to you!

Also I discovered a way to pass null values for parameters which is a bit unorthodox. You check the variable option for the input, but you don't select a variable and then that parameter is excluded from the request.

However there does appear to be one final obstacle which is that the timeout setting doesn't appear to work. Someone with a similar issue posted it at http://connect.microsoft.com/SQLServer/feedback/ViewFeedback.aspx?FeedbackID=277689 and I have validated it.