Service tax input credit in a proprietorship firm

From 01-04-2011 services of personal consumption are disqualified for cenvat credit. Prior to that there are CESTAT decision to support credit of telephone bill if it is used in relation to taxable service/,manufacture of dutiable goods. Vehicle insurance may be allowed if it has nexus with business. Medical insurance is doubtful even under old definition.

You can Avail Service tax credit only those thransaction which purely used for business related ,

Dear Experts

I am doing ship repairs, hence reg under port service category.  I am paying vat on materials used in the job and remaining part i am charging service tax. Since i am not doing trading, materials cannot be billed in the job value as it is hidden in the job value.  But we know materials cost in the total job value, hence after bifurcation, we charge vat as well as service tax. But service tax authorities are not allowing us to get exemption on materials and they want us to charge service tax on total cost. Are they right in saying so? And are we not paying double duty. Can this Materials and Mvat can be taken as input credit?

Please help us

Nandakumar