The ABIv1 toolchain was deprecated in Symbian OS 9.4 but the build system
continued to generate both ABIv1 (.lib) import libraries and ABIv2 (.dso)
import libraries for convenience during the transition to ABIv2.

This change now turns off the generation of ABIv1 import libraries by
default but makes support switchable on a kit-by-kit basis. To turn on
ABIv1 import library generation, add the following setting to the
root.changes variant in epoc32/sbs_config/os_properties.xml

<set name="SUPPORTS_ABIV1_IMPLIBS" value="1"/>

An example properties file is available in the examples/os_properties.xml
file distributed within the Raptor installation.