hobbit not adding negative values to rrd database

Hi
I have a temperature monitor for outside temperature.

i cant get it to work when the temperature is negative.

the rrdtool reports this
<rrd>
        <version> 0003 </version>
        <step> 300 </step> <!-- Seconds -->
        <lastupdate> 1170011401 </lastupdate> <!-- 2007-01-28 20:10:01 CET -->

        <ds>
                <name> Utetemp </name>
                <type> GAUGE </type>
                <minimal_heartbeat> 600 </minimal_heartbeat>
                <min> -4.0000000000e+01 </min>
                <max> NaN </max>

                <!-- PDP Status -->
                <last_ds> UNKN </last_ds>
                <value> 4.0000000000e+00 </value>
                <unknown_sec> 0 </unknown_sec>
        </ds>


if i send positive values it gets updated
but when it is negative nothing happens.

any ideas?

Regards

- Hansi


-- 
Hansi Tesarz
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