Yes, I have tried out the date() method. Although it is part of the rfc, I do not think all servers support it. I've tried it on my private server, which runs leafnode, and it returns undef no matter if I am connected or not. Sample output as follows:

$ perl -MNet::NNTP -MSocket -e '$n=Net::NNTP->new(localhost,Port=>1199
+,Timeout=>10,Debug=>1);print $n->date()||"undef"'
Net::NNTP>>> Net::NNTP(2.22)
Net::NNTP>>>   Net::Cmd(2.24)
Net::NNTP>>>     Exporter(5.562)
Net::NNTP>>>   IO::Socket::INET(1.25)
Net::NNTP>>>     IO::Socket(1.26)
Net::NNTP>>>       IO::Handle(1.21)
Net::NNTP=GLOB(0x826b0b0)<<< 200 Leafnode NNTP Daemon, version 1.9.31.
+rel running at localhost (my fqdn: xxxx.client.attbi.com)
Net::NNTP=GLOB(0x826b0b0)>>> MODE READER
Net::NNTP=GLOB(0x826b0b0)<<< 200 Leafnode 1.9.31.rel, pleased to meet 
+you!
Net::NNTP=GLOB(0x826b0b0)>>> DATE
Net::NNTP=GLOB(0x826b0b0)<<< 500 Unknown command
Net::NNTP=GLOB(0x826b0b0)>>> QUIT
Net::NNTP=GLOB(0x826b0b0)<<< 205 Always happy to serve!
undef

^- output
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