t4 blunder vs. compiling transformation: 'write' member

i'm perplexing category within t4 template vs2008.

here simplified chronicle i'm doing...

<#@ template language="vb" debug="true" hostspecific="true" #>
<#@ cost extension=".vb" debug="true" hostspecific="true" #>
<#@ public name="system.data" #>
<#@ public name="system.windows.forms.dll" #>
<#@ public name="system.xml" #>
<#@ import namespace="system.collections.generic" #>
<#@ import namespace="system.data.sqlclient" #>
<# (new someclass).start()#>
<#+
private category someclass
    open servant start()
    #>test<#+
    finish sub
end category 
#>

when i run template... i following error...

---

error 1 compiling transformation: 'write' member of
'microsoft.visualstudio.texttemplatingf77bde667ecad297f587d3d651053846.
generatedtexttransformation.someclass'. d:\development\privateprojects\codegeneration\codegeneration\generation\common\test2.tt 16 1 codegeneration

can anyone tell since causes blunder does some-more importantly cancel it's effects?