Android debug certificate

Question

I read at android site that "The self-signed certificate used to sign your application in debug mode (the default on Eclipse/ADT and Ant builds) will have an expiration date of 365 days from its creation date."

but when i use jarsigner to take inforamtion about my certificate and write at command line

jarsigner -verify -verbose -certs myapp.apk

i get information that my debug certificate valid time is from 29.08.11 16:07 to 21.08.41 16:07

It's mean that my debug certificate valid 30 years, but it must be valid only 1 years. Maybe this is problem of jarsigner or all is correct? Why so it turns?