fmkt さん、コメントありがとうございます。
指示に従い、確認してみました。やはり挙動が怪しげな気が・・・。
$ sudo RAILS_ENV=production ruby ./script/console
Loading production environment (Rails 2.0.2)
>> >> CustomValue.find(:all,:conditions => ["customized_type = 'Project'"],:select=>:value)
=> []
>> >> CustomField.find(:all)
=> [#<IssueCustomField id: 7, type: "IssueCustomField", name: "CVS
version and files", field_format: "string", possible_values: [],
regexp: "", min_length: 0, max_length: 0, is_required: false,
is_for_all: true, is_filter: true, position: 3, searchable: true,
default_value: "">, #<IssueCustomField id: 8, type:
"IssueCustomField", name: "再現方法", field_format: "text",
possible_values: [], regexp: "", min_length: 0, max_length: 0,
is_required: false, is_for_all: true, is_filter: true, position: 4,
searchable: true, default_value: "">, #<IssueCustomField id: 13, type:
"IssueCustomField", name: "確認者", field_format: "string",
possible_values: [], regexp: "", min_length: 0, max_length: 0,
is_required: false, is_for_all: true, is_filter: false, position: 1,
searchable: false, default_value: "">, #<IssueCustomField id: 14,
type: "IssueCustomField", name: "最終確認者", field_format: "string",
possible_values: [], regexp: "", min_length: 0, max_length: 0, is_req
uired: false, is_for_all: true, is_filter: false, position: 2,
searchable: false, default_value: "">, #<IssueCustomField id: 15,
type: "IssueCustomField", name: "Mailing list", field_format:
"string", possible_values: [], regexp: "", min_length: 0, max_length:
0, is_required: false, is_for_all: false, is_filter: false, position:
5, searchable: false, default_value: "">]
>> >> CustomField.find(:all,:conditions => ["id = 15"])
=> [#<IssueCustomField id: 15, type: "IssueCustomField", name:
"Mailing list", field_format: "string", possible_values: [], regexp:
"", min_length: 0, max_length: 0, is_required: false, is_for_all:
false, is_filter: false, position: 5, searchable: false,
default_value: "">]
>> >> Project.find(:all).map{|project| project.custom_values.find(:all)}
=> [[], [], [], [], []]
>> >> quit
$