floating point operating in vhdl (fixed_pkg)

I write in the modelsim command window for create the ieee_proposed;

vlib ieee_propose

vcom vcom fixed_float_types_c.vhdl

vcom fixed_pkg_c.vhdl

There are no error for line 1 and 2. But, in line 3 this error occur:# ** Error: (vcom-11) Could not find ieee_proposed.fixed_float_types.# ** Error: fixed_pkg_c.vhdl(23): (vcom-1195) Cannot find expanded name "ieee_proposed.fixed_float_types".# ** Error: fixed_pkg_c.vhdl(23): Unknown expanded name.# ** Error: fixed_pkg_c.vhdl(25): VHDL Compiler exiting# C:/altera/10.1/modelsim_ase/win32aloem/vcom failed.

What my false?..thanks for reply