What app is needed to open xfdl files

I don't know where you are obtaining your XFDL file. I suppose there are other files of this "type" but the XFDL files I work with are used by the IBM WebForm Server to generate HTML and Javascript for delivery to web pages. There is also a Form Viewer but, as far as I know, it is not available on the Mac.

Here's a snippet of the XFDL file I am working with "right now" and you can use a text editor to see if yours is similar. If so, then you need a Web Form sever OR Windows with the Form Viewer application installed to read the form:

<?xml version="1.0" encoding="UTF-8"?>

<XFDLxmlns:custom="http://www.ibm.com/xmlns/prod/XFDL/Custom"

xmlns:designer="http://www.ibm.com/xmlns/prod/workplace/forms/designer/2.6"

xmlns:ev="http://www.w3.org/2001/xml-events"

xml:lang="en-CA-u-cu-CAD-x-csymbol-CA$"

xmlns:xfdl="http://www.ibm.com/xmlns/prod/XFDL/8.0"

xmlns:xforms="http://www.w3.org/2002/xforms"

xmlns="http://www.ibm.com/xmlns/prod/XFDL/8.0"

xmlns:xsd="http://www.w3.org/2001/XMLSchema"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

<globalpage sid="global">

<global sid="global">

<designer:date>20130129</designer:date>

<formid>

<title/>

<serialnumber>5F632EFC36469155:-27D490E4:13C86EBBFD2:-7FFF</serialnumber>

<version>1.0.0</version>

</formid>

<pageloading>

<ondemand>enable</ondemand>

</pageloading>

<transmitformat>application/vnd.xfdl;content-encoding=base64-gzip</transmitformat>

<saveformat>application/vnd.xfdl;content-encoding=base64-gzip</saveformat>

<xformsmodels>

<xforms:model functions="matches">

<xforms:instance id="Generated" designer:type="generated" xmlns="">

<data>

<page1>

<referral_list/>

<firstname_input/>

<lastname_input/>

<city_input/>