2549299 - Loading packages file 'packages.xml' failed: undeclared attribute 'signed'

During execution of SWPM (70SWPM SP21,  PL3 and PL4), the following error appears:

In sapinst_dev.log:

ERROR <timestamp> <user account> (startInstallation) [bas/bas/749_REL/bc_749_REL/src/ins/SAPINST/impl/src/cdsrv/CCdManagerPackageXml.cpp:98] id=cdsrv.parserError errno=FCD-00003 CCdManagerPackageXml::readLabelDefinitionFile()
XML parser error. DETAILS: error: undeclared attribute 'signed' [vc: attribute value type] in line <nn>, <nnn>

Unable to start a service execution.The execution will be terminated now.
DETAILS: Loading packages file 'packages.xml' failed:
error: undeclared attribute 'signed' [vc: attribute value type] in line <nn>, <nnn>

• Software Provisioning Manager tool (70SWPM SP21,  PL3 and PL4)
• System based on SAP NetWeaver 7.0x
• Operating System Independent
• Database Independent

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