This is one of those areas where Gtk2's theme engine makes things tricky. Here are a couple of self-explanatory examples.

#!/usr/bin/perl
use warnings;
use strict;
use Gtk2 '-init';

#the Entry settings in ~/.gtkrc-2.0 dosn't
#seem to do anything except create a subtle outline 
#under the entry box. So you need to manually make one. 

Gtk2::Rc->parse_string(<<__);

#include "/usr/local/share/themes/Bumblebee/gtk-2.0/gtkrc"
style "normal" {
  font_name ="serif 30"
}

style "my_entry" {
  font_name ="sans 25"
  text[NORMAL] = "#FF0000"
  text[INSENSITIVE] = "#555555"
}

widget "*" style "normal"
widget "*Entry*" style "my_entry"
__

my $window = Gtk2::Window->new;
$window->set_title("Hello world");
$window->signal_connect( destroy => sub { Gtk2->main_quit; } );

my $vbox = Gtk2::VBox->new();
$vbox->set( "border_width" => 10 );
$window->add($vbox);

my $label = Gtk2::Label->new("ועפשץי");
$vbox->pack_start( $label, 0, 0, 5 );    # expand?, fill?, padding

my $entry = Gtk2::Entry->new();
$vbox->pack_start( $entry, 0, 0, 5 );

my $button = Gtk2::Widget->new( "Gtk2::Button", label => "Set Insensit
+ive" );
$button->signal_connect( clicked => sub { $entry->set_state('insensiti
+ve') } );

my $button1 = Gtk2::Widget->new( "Gtk2::Button", label => "Quit" );
$button1->signal_connect( clicked => sub { Gtk2->main_quit; } );

$vbox->pack_start( $button, 0, 0, 5 );
$vbox->pack_start( $button1, 0, 0, 5 );

$window->show_all();

Gtk2->main;
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#!/usr/bin/perl
use warnings;
use strict;
use Gtk2 '-init';

#the Entry settings in ~/.gtkrc-2.0 dosn't
#seem to do anything except create a subtle outline 
#under the entry box. So you need to manually make one. 

Gtk2::Rc->parse_string(<<__);

include "/usr/local/share/themes/Bumblebee/gtk-2.0/gtkrc"
style "normal" {
  font_name ="serif 30"
}

style "my_entry" {
  font_name ="sans 25"
  text[NORMAL] = "#FF0000"
}

widget "*" style "normal"
widget "*Entry*" style "my_entry"
__

my $window = Gtk2::Window->new;
$window->set_title("Hello world");
$window->signal_connect( destroy => sub { Gtk2->main_quit; } );

my $vbox = Gtk2::VBox->new();
$vbox->set( "border_width" => 10 );
$window->add($vbox);

my $label = Gtk2::Label->new("ועפשץי");
$vbox->pack_start( $label, 0, 0, 5 );    # expand?, fill?, padding

my $entry = Gtk2::Entry->new();
$vbox->pack_start( $entry, 0, 0, 5 );

my $button = Gtk2::Widget->new( "Gtk2::Button", label => "Quit" );
$button->signal_connect( clicked => sub { Gtk2->main_quit; } );

my $button1 = Gtk2::Widget->new( "Gtk2::Button", label => "Toggle Entr
+y Color" );

$button1->signal_connect( clicked => sub { 
         my ( $red, $green, $blue, $color);
       ( $red, $green, $blue) = (int rand 65535, int rand 65535,int ra
+nd 65535 );
       $color = Gtk2::Gdk::Color->new ( $red, $green, $blue);
       $entry->modify_text ( 'GTK_STATE_NORMAL', $color);
       $entry->set_text ("$red $green $blue" );
      } );
 

$vbox->pack_start( $button, 0, 0, 5 );
$vbox->pack_start( $button1, 0, 0, 5 );

$window->show_all();

Gtk2->main;
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