How can I use the "|" pipe (vertical bar) character as a character in TEWS?
As a SOAP request is a specialized form of XML, you have to conform to XML standards for encoding.
https://www.dvteclipse.com/documentation/svlinter/How_to_use_special_characters_in_XML.3F.html
| Vertical bar |
You should encode the vertical pipe character:
<wsdl:TestMultiValuedAttributeObjectProfileTab> <wsdl:_BAR_multi_valued_attribute_BAR_>one|two|three</wsdl:_BAR_multi_valued_attribute_BAR_> </wsdl:TestMultiValuedAttributeObjectProfileTab>