lsapi not compatible with ruby 1.9.1 ?

[Grzegorz Derebecki]

/opt/ruby19/bin/ruby extconf.rb install ruby-lsapi
checking for main() in -lsocket... no
creating Makefile

make
gcc -I. -I/opt/ruby19/include/ruby-1.9.1/i386-darwin10.2.0 -I/opt/ruby19/include/ruby-1.9.1/ruby/backward -I/opt/ruby19/include/ruby-1.9.1 -I. -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -fno-common -O2 -g -Wall -Wno-parentheses -pipe -fno-common -o lsapilib.o -c lsapilib.c
gcc -I. -I/opt/ruby19/include/ruby-1.9.1/i386-darwin10.2.0 -I/opt/ruby19/include/ruby-1.9.1/ruby/backward -I/opt/ruby19/include/ruby-1.9.1 -I. -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -fno-common -O2 -g -Wall -Wno-parentheses -pipe -fno-common -o lsruby.o -c lsruby.c
In file included from lsruby.c:3:
/opt/ruby19/include/ruby-1.9.1/ruby/backward/util.h:2:2: warning: #warning use "ruby/util.h" instead of bare "util.h"
lsruby.c: In function 'lsapi_write':
lsruby.c:257: error: 'struct RString' has no member named 'ptr'
lsruby.c:257: error: 'struct RString' has no member named 'len'
lsruby.c: In function 'lsapi_puts_ary':
lsruby.c:310: error: 'struct RArray' has no member named 'len'
lsruby.c:312: error: 'struct RArray' has no member named 'ptr'
lsruby.c:313: warning: implicit declaration of function 'rb_inspecting_p'
lsruby.c: In function 'lsapi_puts':
lsruby.c:341: warning: implicit declaration of function 'rb_protect_inspect'
lsruby.c:349: error: 'struct RString' has no member named 'ptr'
lsruby.c:349: error: 'struct RString' has no member named 'len'
lsruby.c: In function 'lsapi_gets':
lsruby.c:413: error: 'struct RString' has no member named 'len'
lsruby.c: In function 'lsapi_read':
lsruby.c:458: error: 'struct RString' has no member named 'len'
make: *** [lsruby.o] Error 1