$ lpstat -p
printer Brother_MFC_9840CDW is idle.  enabled since Mon 12 Oct 2009 07:47:12 AM EDT
printer CUPS-PDF is idle.  enabled since Wed 02 Sep 2009 05:59:48 AM EDT
printer Deskjet-5900-series disabled since Thu 08 Oct 2009 08:03:28 PM EDT -
        reason unknown
printer DESKJET-970C disabled since Mon 12 Oct 2009 08:01:00 AM EDT -
        reason unknown
printer DESKJET-970C2 disabled since Mon 12 Oct 2009 08:01:11 AM EDT -
        reason unknown

As you see, there is also another HP printer - 970C2, which is also disabled. cups-printers' output:

$ cups-printers
Found printer "Brother_MFC_9840CDW", "(null)"
        Option "copies"="1"
        Option "job-hold-until"="no-hold"
        Option "job-priority"="50"
        Option "number-up"="1"
        Option "auth-info-required"="none"
        Option "printer-info"="Brother MFC-9840CDW"
        Option "printer-is-accepting-jobs"="1"
        Option "printer-is-shared"="0"
        Option "printer-location"="Location Unknown"
        Option "printer-make-and-model"="Brother MFC-9840CDW CUPS on 10.0.1.194"
        Option "printer-state"="3"
        Option "printer-state-change-time"="1255348032"
        Option "printer-state-reasons"="none"
        Option "printer-type"="18919518"
Found printer "CUPS-PDF", "(null)"
        Option "media"="A4"
        Option "finishings"="3"
        Option "copies"="1"
        Option "job-hold-until"="no-hold"
        Option "job-priority"="50"
        Option "number-up"="1"
        Option "auth-info-required"="none"
        Option "job-sheets"="none,none"
        Option "printer-info"="Virtual PDF Printer"
        Option "printer-is-accepting-jobs"="1"
        Option "printer-is-shared"="1"
        Option "printer-location"="Local Printer"
        Option "printer-make-and-model"="Generic CUPS-PDF Printer"
        Option "printer-state"="3"
        Option "printer-state-change-time"="1251885588"
        Option "printer-state-reasons"="none"
        Option "printer-type"="61516"
Found printer "Deskjet-5900-series", "(null)"
        Option "media"="A4"
        Option "sides"="one-sided"
        Option "finishings"="3"
        Option "copies"="1"
        Option "job-hold-until"="no-hold"
        Option "job-priority"="50"
        Option "number-up"="1"
        Option "auth-info-required"="none"
        Option "job-sheets"="none,none"
        Option "printer-info"="HP Deskjet 5900 series"
        Option "printer-is-accepting-jobs"="0"
        Option "printer-is-shared"="1"
        Option "printer-location"="xpack"
        Option "printer-make-and-model"="HP Deskjet 5900 series Foomatic/hpijs, hpijs 2.8.6b"
        Option "printer-state"="5"
        Option "printer-state-change-time"="1255046608"
        Option "printer-state-reasons"="paused"
        Option "printer-type"="528412"
Found printer "DESKJET-970C", "(null)"
        Option "media"="A4"
        Option "sides"="one-sided"
        Option "finishings"="3"
        Option "copies"="1"
        Option "job-hold-until"="no-hold"
        Option "job-priority"="50"
        Option "number-up"="1"
        Option "auth-info-required"="none"
        Option "job-sheets"="none,none"
        Option "printer-info"="HEWLETT-PACKARD DESKJET 970C"
        Option "printer-is-accepting-jobs"="0"
        Option "printer-is-shared"="1"
        Option "printer-location"="xpack"
        Option "printer-make-and-model"="HP Deskjet 970c Foomatic/hpijs, hpijs 2.8.6b"
        Option "printer-state"="5"
        Option "printer-state-change-time"="1255348860"
        Option "printer-state-reasons"="paused"
        Option "printer-type"="528412"
Found printer "DESKJET-970C2", "(null)"
        Option "media"="A4"
        Option "sides"="one-sided"
        Option "finishings"="3"
        Option "copies"="1"
        Option "job-hold-until"="no-hold"
        Option "job-priority"="50"
        Option "number-up"="1"
        Option "auth-info-required"="none"
        Option "job-sheets"="none,none"
        Option "printer-info"="HEWLETT-PACKARD DESKJET 970C"
        Option "printer-is-accepting-jobs"="0"
        Option "printer-is-shared"="1"
        Option "printer-location"="xpack"
        Option "printer-make-and-model"="HP Deskjet 970c Foomatic/hpijs, hpijs 2.8.6b"
        Option "printer-state"="5"
        Option "printer-state-change-time"="1255348871"
        Option "printer-state-reasons"="paused"
        Option "printer-type"="528412"

Does it depend on hpijs version? In Debian Lenny hpijs is "2.8.6b".