Unknown rule in CALL

[sebastiansutter]

I added the policy to my 5.0.8.1 environment. When using the policy in an API, it returns HTTP 500. The DataPower log shows the following:

mpgw (webapi): api-error-response multistep error

2:29:53 PM | mpgw | error | 4785 | error | 192.168.225.1 | 0x00d30003 | mpgw (webapi): Rejected by filter; SOAP fault sent
2:29:53 PM | multistep | error | 4785 | request | 192.168.225.1 | 0x80c00009 | mpgw (webapi): request webapi-mpgw-request-fw #8 Calling rule var://context/policy/fw/call-rule with input NULL and output NULL. failed: Unknown rule in CALL
2:29:53 PM | multistep | error | 4785 | request | 192.168.225.1 | 0x80c00009 | mpgw (webapi): request webapi-policy-step-fw-invoke-xform #5 Calling rule var://context/policy/fw/call-rule with input NULL and output NULL. failed: Unknown rule in CALL
2:29:53 PM | multistep | error | 4785 | request | 192.168.225.1 | 0x80c00009 | mpgw (webapi): request webapi-policy-step-fw-invoke-rule #5 Calling rule var://context/policy/fw/call-rule with input NULL and output NULL. failed: Unknown rule in CALL
2:29:53 PM | multistep | error | 4785 | request | 192.168.225.1 | 0x80c00009 | mpgw (webapi): request webapi-policy-end #1 xform: Transforming the content of NULL. The transformation local:///isp/policy/apim.policy.end.xsl is applied. The results are stored in NULL. failed: Unknown rule in CALL
2:29:53 PM | multistep | error | 4785 | request | 192.168.225.1 | 0x80c00009 | mpgw (webapi): request webapi-policy-step-fw-invoke-rule #2 Calling rule var://context/policy/exec with input NULL and output policy-output-temp. failed: Unknown rule in CALL