Self signed certs with nginx

[Wayne E. Seguin]

I used the following command to generate a self signed cert:

openssl req -new -newkey rsa:1024 -days 365 -nodes -x509 -keyout  
domainname.tld.key -out domainname.tld.com.crt

I then restarted nginx and tried to access the page via https and  
received an "ErrorCode: 12263" in firefox which translates to  
"SSL_ERROR_RX_RECORD_TOO_LONG".

I have used this method fine in apache 2.2 before.
What is the proper procedure for creating a self signed cert for nginx?

   ~Wayne