Classpath and JamVM on openwrt 19.07


I am trying to build the jamVM with classpath for openwrt-x86_64. I am encountring below error related to CLASSPATH. Dont know if i need to set CLASSPATH somewhere or what!!

checking for cacao... no
checking for jamvm... jamvm
checking for ecj... ecj -warn:-deprecation,serial,unusedImport
checking if ecj -warn:-deprecation,serial,unusedImport is a version of gcj... no
checking if ecj -warn:-deprecation,serial,unusedImport works... yes
checking for uudecode... no
configure: WARNING: I have to compile Test.class from scratch
checking if jamvm works... configure: error: The Java VM jamvm failed (see config.log, check the CLASSPATH?)