pfSense

When creating Limiters the GUI allows delay values above 10000ms. The config also allow this and it is written into the generated ipfw ruleset:

        <queue>
            <name>15seconds</name>
            <number>2</number>
            <qlimit></qlimit>
            <plr></plr>
            <description></description>
            <bandwidth>
                <item>
                    <bw>1</bw>
                    <burst></burst>
                    <bwscale>Kb</bwscale>
                    <bwsched>none</bwsched>
                </item>
            </bandwidth>
            <enabled>on</enabled>
            <buckets></buckets>
            <mask>none</mask>
            <maskbits></maskbits>
            <maskbitsv6></maskbitsv6>
            <delay>15000</delay>
            <sched>wf2q+</sched>
            <aqm>droptail</aqm>
            <ecn></ecn>
        </queue>

pipe 2 config  bw 1Kb delay 15000 droptail
sched 2 config pipe 2 type wf2q+

However ipfw/dummynet does not allow delays longer than 10000ms:

[2.4.4-RELEASE][admin@7100.stevew.lan]/root: ipfw pipe 6 config delay 15000ms
ipfw: delay must be < 10000

The defined pipe is therefore not created. Worse is that ipfw stops processing the ruleset at that point so any pipes defined after that are also not created.
This results in any rules using those pipes just dropping the matched traffic.