This is standard situation for Delphi6. Add a reference to DesignIDE.dcp in usage part of the package. Do not forget also to change package options to 'Design time only' and 'Rebuild as needed', this is certain for any other Delphi version too (starting from Delphi3).

这是 delphi6 的标准状况. 在 package 的 usage 部分加入一个对 DesignIDE 的引用. 不要忘记还要把 package option 改成 "Design time only" 和 "Rebuild as needed". 对于别的 Delphi 版本(从 delphi3 开始) 都是这样的.