Postfix still accepting non FQDN

[PcPixel2002]

I'm looking to deploy a Postfix server in place of a sendmail server after reading up on how Postfix works. I've got the system so it can deliver mail locally, but now I'm looking to add security (gradually) to the Postfix install. I'm trying to test out the server accepting FQDNs only. I telnet to the system & issue a: HELO sparky . If I continue composing the email in telnet, it happily accepts everything. What am I doing wrong? This is my Postfix configuration to date:
================================================== ======
queue_directory = /var/spool/postfix
command_directory = /usr/sbin
daemon_directory = /usr/libexec/postfix
mail_owner = postfix
default_privs = nobody

myhostname = postfix.quirkygames.com
mydomain = quirkygames.com
myorigin = $mydomain
mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain
mynetworks_style = class
inet_interfaces = all

relay_domains = $mydestination

alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases

unknown_local_recipient_reject_code = 550

debugger_command =
PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
xxgdb $daemon_directory/$process_name $process_id & sleep 5

sendmail_path = /usr/sbin/sendmail.postfix
newaliases_path = /usr/bin/newaliases.postfix
mailq_path = /usr/bin/mailq.postfix

setgid_group = postdrop
html_directory = no
manpage_directory = /usr/share/man
#================================================= ========
smtpd_delay_reject = yes
smtpd_helo_required = yes

smtpd_helo_restrictions =
permit_mynetworks,
reject_invalid_hostname,
reject_non_fqdn_hostname,
permit

smtpd_recipient_restrictions =
permit_mynetworks,
reject_invalid_hostname,
reject_non_fqdn_hostname,
permit

==================================================
If I activate just the helo restrictions, it lets the email complete. If I enable the recipient restrictions, the moment I telnet to port 25, the cursor just hangs.

Any help would be appreciated.

[PcPixel2002]

Someone pointed out my problem:

Postfix still accepting non FQDN - LinuxQuestions.org

Now I have another question: why would the postfix book I'm reading claim that the fqdn restriction should be in the smtpd_recipient_restrictions ?

And also, if I use the smtpd_recipient_restrictions then when I telnet to the system, my telnet session locks up totally. I don't even get the SMTP greeting.

Why would that happen?