Classification creation fails with: Missing classification

[sufo]

I'm trying to create my own classification via the WebScript but it fails with the error message: Missing classification: {travel.agency.model}taclassifiable
I have defined my own model (<namespace uri="travel.agency.model" prefix="ta"/>) in which there is this aspect defined:

      <aspect name="ta:taclassifiable">
         <title>Travel Agency Classifiable</title>
         <parent>cm:classifiable</parent>
         <properties>
            <property name="ta:categories">
               <title>Categories</title>
               <type>d:category</type>
               <mandatory>false</mandatory>
               <multiple>true</multiple>
               <index enabled="true">
                  <atomic>true</atomic>
                  <stored>true</stored>
                  <tokenised>false</tokenised>
               </index>
            </property>         
         </properties>
      </aspect>‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

When I try to execute this code, it generates above mentioned error:

var categoryRoot = roothome.childByNamePath("categories");
var props = [];
props["view:childName"] = "{travel.agency.model}taclassifiable";
var classification = categoryRoot.createNode("taclassifiable", "cm:category", props, "cm:categories");
‍‍‍‍‍

Am I missing something?

[sufo]

Found the solution, I replaced last line of the code and removed 'view:childName' property:

var categoryRoot = roothome.childByNamePath("categories");
var props = [];
var classification = categoryRoot.createNode("{travel.agency.model}taclassifiable", "cm:category", props, "cm:categories", "{travel.agency.model}taclassifiable");‍‍‍

This line also works:

var classification = categoryRoot.createNode("taclassifiable", "cm:category", props, "cm:categories", "ta:taclassifiable");‍