convert PEM Certificate or Java Certificate to ASN1 Certificate
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I have a certificate in a PEM file. 
I want to construct a CMPCertificate from this file. So I have to build an org.bouncycastle.asn1.x509.Certificate in order to call CMPCertificate.getInstance(...). 

How could I convert a PEM file or a java.security.cert.Certificate to org.bouncycastle.asn1.x509.Certificate ?

Thanks for your help, 
Vincent