Java Security

Has anyone had much luck using a Java keystore in PKCS12 format? I work at a company where we use this format to store SSL certificates. Unfortunately keytool doesn't seem to work well with it. I have a certificate chain in DER format, and I am trying to import the file into our keystore.

keytool -import -alias aliasname -file vChain.cer -keystore keystore.p12 -storetype pkcs12
Enter keystore password:
...snip...
Trust this certificate? [no]: yes
keytool error: java.security.KeyStoreException: TrustedCertEntry not supported

Is it possible to import a DER or PEM certificate into a PKCS12 keystore? I have tried using openssl to convert the certificate into PKCS12 format before importing, but that doesn't work either, because it complains about not finding a private key.

Any help would be appreciated! Thanks.