SoaML Toolbox Pages
You can create the elements and relationships of the SoaML model using the SoaML pages of the Diagram Toolbox. Each of the two SoaML diagram types has a separate set of pages, although the last five (SOA-specific) pages in the two sets are identical.
Access Diagram | Toolbox (Alt+5) | More tools | SoaML Component, or SoaML Sequence
SoaML Component Diagram Toolbox
SoaML Sequence Diagram Toolbox