Eclipse Java Compile Issue

[lakecat]

I have an iterative robot project that I split up into a number of packages. I added two extra packages underneath the usual org.usfirst.frc.team2635.robot package. Before splitting the project into packages, I was able to upload to the robot just fine. Now when I try to run, I get a long string of build errors like this:

compile:
    [mkdir] Created dir: C:\Users\localuser\Desktop\workspace\LiftBotJava\build
     [echo] [athena-compile] Compiling src with classpath=${wpilib.jar}:${networktables.jar} to build
    [javac] Compiling 26 source files to C:\Users\localuser\Desktop\workspace\LiftBotJava\build
    [javac] C:\Users\localuser\Desktop\workspace\LiftBotJava\src\org\usfirst\frc\team2635\robot\IElevationSetter.java:3: error: package edu.wpi.first.wpilibj does not exist
    [javac] import edu.wpi.first.wpilibj.SpeedController;
    [javac]                             ^
    [javac] C:\Users\localuser\Desktop\workspace\LiftBotJava\src\org\usfirst\frc\team2635\robot\IElevationSetter.java:7: error: cannot find symbol
    [javac] 	void setLiftElevation(Double setPoint, SpeedController lift1, SpeedController lift2);
    [javac] 	                                       ^
    [javac]   symbol:   class SpeedController
    [javac]   location: interface IElevationSetter
    [javac] C:\Users\localuser\Desktop\workspace\LiftBotJava\src\org\usfirst\frc\team2635\robot\IElevationSetter.java:7: error: cannot find symbol
    [javac] 	void setLiftElevation(Double setPoint, SpeedController lift1, SpeedController lift2);
    [javac] 	                                                              ^
    [javac]   symbol:   class SpeedController
    [javac]   location: interface IElevationSetter

And so on for 100 errors. Has anyone else had this problem?